Materials

Solution/Model Answer to VTU question paper (JUlN-JUL 2019 exam) is linked at the last of this page

Solution/Model Answer to current sem IATs, VTU question paper (Jan 2019 exam) is linked at the last of this page

Solution of 25 important question questions is linked at last of this page

Last experiment of lab - Binary to Decimal using recursion

/* Binary to decimal using recursion-Dr. P. N. Singh */

#include <stdio.h>

int len=0;

int bintodec(char binary[], int pos)

{

int temp;

if (pos == len)

return (binary[pos] - '0');/* ASCII '0'-'0'=0 and '1'-'0'=1 */

/* Left shift & Add current, recur for remaining digits*/

temp=(binary[pos]-'0') << (len-pos);

return (temp + bintodec(binary,pos+1));

}

int main()

{

char bin[100];

printf("Enter binary digits(0 & 1):");

scanf("%s",bin);

while(bin[len]!=NULL) len++;

len=len-1; /* coming before NULL*/

printf("Decimal equivalent = %d\n",bintodec(bin,0));

return (0);

}

Module 1 : Computer fundamentals notes/Important points

2^nd Sem: CPS : Dr. P. N. Singh,Professor(CSE)

Computer Generations

Classification/Types of computers:

According to purpose:

a. Analog computers: Analog computer is a form of computer that is used to read & measure the physical phenomena such as electrical, mechanical, or hydraulic quantities (Not discrete) . Eg. Thermometer, Speedometer, Morse code Telex Machine, amplifiers etc.

b. Digital Computer: A computer that performs calculations and logical operations with quantities represented as digits, usually in the binary number system. Example: Calculator, laptops, PCS

c. Hybrid Computer: A combination of analog and digital computers those are capable of inputting and outputting in both digital and analog signals. A hybrid computer system setup offers a cost effective method of performing complex simulations. Here calculations are done digitally and actions are taken mechanically or vice-versa. Super computers and robots are hybrid computers.

According to size:

a. Super Computer: They are very large and very fast & task specific computers used by large organizations. These computers are used for weather forecasting, meteorology, earth-quack studies, research and exploration purposes. Super computers may be installed in satellites. NASA uses supercomputers for launching space shuttles, controlling them and for space exploration purpose. Example: Titan, Cray( of India)

b. Mainframe Computer: These are smaller and less faster than super computers. Large firms & government organizations like banks, railways use Mainframes to run their business operations in their head/central office as a central role to update day to day transactions. Using virtual machines, mainframes run the various operating systems as if they were running on different computers. Example z9, z10

c. Mini Computers: Minicomputers are used by small businesses & firms. Minicomputers are also called as “Midrange Computers”. Individual departments of a large company or organizations use Mini-computers for specific purposes. Example K202, IBM Midrange

d. Micro Computers: Desktop computers, laptops, PCs, personal digital assistant (PDA), tablets & Smartphones, Scientific Clculators, Notebook, Gaming console, Sound and navigation System are all types of microcomputers. The micro-computers are widely used & the fastest growing computers. Well known manufacturers are Dell, Apple, Samsung, Sony etc.

Bits & Bytes, Words: Number System

Ports & Connectors:

PS/2 (Personnel System 2) port

Serial Port

Parallel Port

S/P DIF (Sony/Philips Digital Interface)

VGA(Visual/Video Graphics Array/Adaptor) (Digital Visual Interface)

USB ((Universal Serial Bus) (Display port)

eSATAp (e-Serial Advanced Technology Port, Serial May be replaced by Parallel)

Wi-fi- Wireless Fidelity

Different files abbreviations

PDF : Printer Definition File or Portable Document Format

PNG: Portable Network Graphics

TIFF: tagged ImageFile Format

JPEG: Joint Picture/Photograhic Experts Group

PSD: Photoshop Document

GIF: Graphic Interchange Format

EPS: Encapsulated Postscripts

AI: Adobe Illustrator

Computer Network: computer network is a set of computers connected together for the purpose of sharing resources. The most common resource shared today is connection to the Internet. Other shared resources can include a printer or a file server. The Internet itself can be considered a computer network.

Basic Network Hardware

Network Cables: Network cables are the transmission media to transfer data from one device to another. A commonly used network cable is category 5 cable with RJ – 45 connector, as shown in the image below:

Routers: A router is a connecting device that transfers data packets between different computer networks. Typically, they are used to connect a PC or an organization’s LAN to a broadband internet connection. They contain RJ-45 ports so that computers and other devices can connect with them using network cables.

Repeaters, Hubs, and Switches : Repeaters, hubs and switches connect network devices together so that they can function as a single segment.

A repeater receives a signal and regenerates it before re-transmitting so that it can travel longer distances.

A hub is a multiport repeater having several input/output ports, so that input at any port is available at every other port.

A switch receives data from a port, uses packet switching to resolve the destination device and then forwards the data to the particular destination, rather than broadcasting it as a hub.

Bridges: A bridge connects two separate Ethernet network segments. It forwards packets from the source network to the destined network.

Gateways: A gateway connects entirely different networks that work upon different protocols. It is the entry and the exit point of a network and controls access to other networks.

Network Interface Cards : NIC is a component of the computer to connect it to a network. Network cards are of two types: Internal network cards and external network cards.

Languages & Protocols:

DNS: Domain Name System

FPT: File transfer Protocol

HTML (Hypertext markup Language)

HTTP(Hyper text Transmission Protocol)

TCP(Transmission Control Protocol)

IP(Internet Protocol)

SAP(Service Access Point)

IPv4 (Internet Protocol version 4): 4 octats

Software Basics

Types of software:

System Software

Application Software:

Utility Software

Generation Programming Languages: “Every age has a language of its own”

1. The first generation languages, or 1GL, are low-level languages that are machine language (0s & 1s).

2. The second-generation languages, or 2GL, are also low-level assembly languages. They are sometimes used in kernels and hardware drives, but more commonly used for video editing and video games.

Assembly Language Mnemonic Codes: (ADD, MUL)

Up to 2^nd generation the languages were machine dependent.

3. The third-generation languages, or 3GL, are high-level languages, such as C, C++, Java, JavaScript, and Visual Basic.

4. The fourth-generation languages, or 4GL, are languages that consist of statements similar to statements in a human language. Fourth generation languages are commonly used in database programming and scripts examples include Perl, PHP, Python, Ruby, and SQL.

5. The fifth-generation languages, or 5GL, are programming languages that contain visual tools to help develop a program. Examples of fifth generation languages include Mercury, OPS5, and Prolog.

Programming Terms:

Source Code

Editor

IDE (Integrated Development Environment)

Object File

Executable File

Working with OS / Few OS Commands

ls

date

cat

cp

cd

rmdir

rm

mv

wc

gedit

….

Understanding PATH of file/directory

To compile a C Program: cc/gcc filename.c

To run last compiled C program : ./a.out

Model Answer/Solution to VTU Question

CBCS-17PCD23-Programming In C & Data Structure – June 2018

Dr. P. N. Singh, Professor(CSE), CMRIT, Bangalore

Q 1 a) Write basic structure of C Program and explain its different sections. 8 M

Ans:

Structure of a C program

· Documentation Section: This section is used to write Problem, file name, developer, date etc in comment lines within /*….*/ or separate line comments may start with // . Compiler ignores this section. Documentation enhances the readability of a program.

· Link section : To include header and library files whose in-built functions are to be used. Linker also required these files to build a program executable. Files are included with directive # include

· Definition section: To define macros and symbolic constants by preprocessor directive #define

· Global section: to declare global variables – to be accessed by all functions

· main() is the user defined function which is recognized by the compiler first. So, all C program must have user defined function main() { …………. }. It should have declaration part first then executable part.

· Sub program section: There may be other user defined functions to perform specific task when called.

/* Example: a program to find area of a circle – area.c

Dr. P. N. Singh - Documentation Section*/

#include <stdio.h> /* - Link/Header Section */

#define PI 3.14 /* definition/global section*/

int main() /* main function section */

{

float r, area; /* declaration part */

printf(“Enter radius of the circle : “); /* Execution part*/

scanf(“%f”, &r);

area=PI*r*r; /* using symbolic constant PI */

printf(“Area of circle = %0.3f square unit\n”, area);

return (0);

}

Q 1 b) What are rules to be followed to declare an identifier with example. 4 M

Ans:

Identifiers - Names of variables, function, or arrays are identifiers.

Rules to construct identifier:

è They may contain A-Z, a-z, and _ (underscore) (no blanks)

è An identifier name but must be started with an alphabet or _ (specific purposes)

è Maximum length of name of identifier should be 31 characters (ANSI C standards) however in newer versions length of identifier name may be more.

è Keywords & compiler constants should not be identifier name

Valid identifiers: num1, a_2

Invalid identifiers: $num1, for, 1^st_paper_marks

Q 1 c) Write a note on different types of type conversions, with an example program for each. 8 M

Ans:

Type conversion concept in C language is used to modify a variable from one date type to another data type. New data type should be mentioned before the variable name or value in brackets which to be typecast.

Example:

result = (float) 20/3;

· It is best practice to convert lower data type to higher data type to avoid data loss.

· Data will be truncated when higher data type is converted to lower. For example, if float is converted to int, data which is present after decimal point will be lost

Type conversion can be done 2ways:

a) Implicit Type conversion / Coercion / Automatic type conversion

It is done by compiler automatically:

example:

printf(“%f”, 20/3.00);

b) Explicit Type conversion / A cast

By preceding the expression with type in parenthesis

It may be checked, unchecked or bit pattern.

Syntax:

(type) expression;

Q 2 a) Define C – tokens. List & explain different C - Tokens. 8 M

Ans:

• Valid Characters (alphabets, numbers or symbols) used in C program are known as C – tokens.

• Each and every smallest individual units in a C program are known as C tokens.

• C tokens are the basic buildings blocks in C language which are constructed together to write a C program.

C tokens are of six types. They are,

1. Keywords (eg: int, while),

2. Identifiers (eg: main, total),

3. Constants (eg: 10, 20),

4. Strings (eg: “total”, “hello”),

5. Special symbols (eg: (), {}),

6. Operators (eg: +, /,-,*)

Example program for C - Tokens

int main()

{

int x, y, sum;

x = 10, y = 20;

sum = x + y;

printf ("Total = %d \n", sum);

}

where,

• main – identifier

• {,}, (,) – delimiter

• int – keyword

• x, y, sum – identifier

• main, {, }, (, ), int, x, y, sum – tokens

Q 2 b)Write a C program to convert number of days into months and days. (Hint: Assume a month has 30 days) (For e.g. 45 days = 1 month 15 days) 4 M

Ans:

/* number of days into months and days */

#include <stdio.h>

int main()

{

int days,ndays,months;

printf("Enter number of days : ");

scanf("%d",&days);

months = days/30;

ndays=days%30; /* remainder by dividing 30 */

printf("%d days = %d months and %d days\n",days,months,ndays);

return (0);

}

Expected Output:

Enter number of days : 987

987 days = 32 months and 27 days

Q 2 c) Write a note on Operators precedence and associativity: 8 M

Ans:

Operator Precedence:

· If more than one operators are involved in a single expression, C language has a predefined rule of priority for the operators. This rule of priority of operators is called Operators precedence.

Example1:

printf(“%d”, 3 % 10 + 5); /* gives the output 8 */

Explanation: Modulas operator % has greater precedence than addition +. So, 3 % 10 will be 3 and adding 5 will give the result 8

Example2:

printf(“%d”, 3 + 4>5); /* gives the output 1 and not 3 */

Explanation: Arithmetic operator has greater precedence than relational operator so, 3 will be added with 4 first then 7 will be compared with 5 which gives the boolean output 1.

Example 3:

printf(“%d”, 1 > 2 + 3 && 4);

This expression is equivalent to:

((1 > (2 + 3)) && 4)

i.e, (2 + 3) executes first resulting into 5

then, first part of the expression (1 > 5) executes resulting into 0 (false)

then, (0 && 4) executes resulting into 0 (false)

· In C, precedence of arithmetic operators( *, %, /, +, -) is higher than relational operators(==, !=, >, <, >=, <=) and precedence of relational operator is higher than logical operators(&&, || and !).

ii) Associativity:

If two operators of same precedence (priority) is present in an expression, Associativity of operators indicate the order in which they execute (left to right or right to left).

Most of the operators have the asociativity left to right.

Example 1:

printf(“%d”, 10/5/2); /* output 1 – There should not be confusion that 10 is divided by 5/2 */

Example 2:

printf(“%d”, 1==2 !=3); /* output 1, 1==2 will give 0 and 0 != 3 will give 1 */

increment and decrement operators have associativity from right to left:

Example:

int n=7;

printf(“%d %d %d”,n++,n++,n++); /* gives output 9 8 7 and not 7 8 9 */

Q 3 a) An electric power distribution company charges its domestic consumers as follows: 8 M

/*stack push() operation given in a function */

void push(int stack[], int item)

{

if(top==size-1)

print(“Stack is full-overflow.\n”);

else

{

top++;

stack[top]=item;

}

}

/*stack push() operation given in a function */

int pop(int stack[])

{

int d;

if(top==-1)

{

printf(“Stack is empty-underflow\n”);

return (NULL);

}

else

{

d=stack[top];

stack[top]=NULL;

top--;

return (d);

}

}

Q 10 b) Write a C program which copies contents of a string to another using pointer as function parameter. Print copied string. 8 M

Ans:

/* string copy using pointer as function parmeter */

#include <stdio.h>

#include <stdlib.h>

void strkopy(char *source, char *target) /*char pointer as parameter*/

{

int x;

for(x=0;*(source+x)!=NULL;x++)

*(target+x) = *(source+x); /* copying character by character */

*(target+x)=NULL; /* last character NULL */

}

int main()

{

char *str1, *str2;

str1=malloc(50); /* allocating memory 50 bytes for each */

str2=malloc(50);

printf("Enter source string : ");

gets(str1);

strkopy(str1,str2); /* calling function passing reference */

printf("Copied string is %s\n",str2);

return (0);

}

Expected Output:

Enter source string : Yuvraj Singh

Copied string is Yuvraj Singh

Q 10 c): Mention Significance of Compiler Control Pre-Processor Directives. 4 M

Ans:

· Compiler control directives: These are conditional directives and may be written within program also. For example whether a macro is defined or not we can check it within program and redefine (general directives also) if required. Mostly #if family directives are of this category.

Examples: #if, #endif, #else, #ifdef, #ifndef

#ifdef

#ifdef preprocessor directives checks whether a macro is defined by #define. If yes, it executes

the code:

Example:

#ifdef PI

Printf(“PI symbolic constant is already defined\n”);

#endif

#ifndef

#ifndef preprocessor directives checks whether a macro is not defined by #define. If yes, it

executes the code:

Example:

#ifndef PI

#define PI 3.14

#endif

#else : it is used for alternative where #if, #ifdef or #ifndef condition is not satisfied:

#ifdef PI

printf(“PI symbolic constant is already defined\n”);

#else

#define PI 3.14

#endif

Solution/Model Answer to IAT-3

Programming in C & data Structure

2^nd Sem I & J Section

-Dr. P. N. Singh, Professor(CSE)

1 a) Develop(write) a C program to display contents of a text file. (File name is given by user. Display appropriate error message if the file does not exist.) 05m

Ans:

/* dikhao.c - To display the contents of a text file */

#include <stdio.h>

int main()

{

FILE *fp;

char fname[64],c;

printf("Enter file name : ");

scanf("%s",fname);

fp=fopen(fname,"r");

if(!fp)

{

printf("File %s does not exist.\n",fname);

return (99);

}

printf("Contents of %s file:\n");

while(!feof(fp))

{

c=fgetc(fp);

putchar(c);

}

fclose(fp);

return (0);

}

1 b) Write a C program to copy contents of a file to another file. 05

/* kopy.c */

#include <stdio.h>

int main()

{

FILE *fp1, *fp2;

char sfname[64],tfname[64],c;

printf("Enter source file name : ");

scanf("%s",sfname);

fp1=fopen(sfname,"r"); /*opening source file with read permission.*/

if(!fp1){

printf("File %s does not exist\n",sfname);

return (99);

}

printf("Enter target file name : ");

scanf("%s",tfname);

fp2=fopen(tfname,"w"); /* opening target file with write permission*/

while(!feof(fp1))

{

c=fgetc(fp1); /* copying character by character in target file*/

fputc(c,fp2);

}

fclose(fp1);

fclose(fp2);

return (0);

}

2. Define file handling functions fgetc(), fputc(), fprintf(), fscanf(), fopen() with syntax and examples. 10

Ans:

fgetc( ) – reads a character from a file and moved the file pointer one character forward:

example:

c=fgetc(fp);

Reads a character from file pointed by file pointer fp and stores in character variable c

fputc( ) – Writes a character to a file and moved the file pointer one character forward:

example:

fputc(c, fp);

Writes character of c variable in file pointed by fp and moves the file pointer for next

Reads a character from file pointed by file pointer fp and stores in character variable c

fprintf( ) – formatted output to a file

Syntax: fprintf ( fp, “control string”, var1,var2,..varn);

file pointer variable,constants, strings

Example: fprintf( f1, “%s %d %f\n ”, name, age, 7.8);

fscanf( ) – formatted input from file

Syntax: fscanf(fp, “control string”, &var1, &var2,….&varn);

Example: fscanf(f2, “ %s %d”, item, &qtty);

fopen( ) – opens file different modes

Syntax:

FILE *fp;

fopen(filename,”mode”)

Example:

fp=fopen(“student.txt”,”r”);

File opening modes:

r-read only

w-write

a-append

3 a)

What are following declarations:

i. int *a[5];

ii. int (*p)[5];

iii. int *func( );

iv. int (*func)( ); 5m

Ans:

i. int *a[5];

/* Array of pointers - an array having all 5 element addresses only */

ii. int (*p)[5];

/*Pointer to arrays – Here p is pointer to 2-d array where 5 is number of columns */

iii. int *func( );

/*Pointer to return type of function – The function func() will return address */

iv. int (*func)( );

/* Pointer to function – here func pointer will keep address of other function */

3 b) Implement call by reference in a C program using pointers. 5 m

/* Call by reference using pointers */

#include <stdio.h>

void swap(int *p, int *q) /* here p and q are receiving addresses */

{

int temp = *p;

*p = *q;

*q = temp;

}

int main()

{

int num1, num2;

printf(“Enter number 1 : “);

scanf(“%d”, &num1);

printf(“Enter number 2 : “);

scanf(“%d”, &num2);

swap(&num1, &num2); /& call by reference */

printf(“Numbers swapped: num1 = %d num2 = %d\n”, num1, num2);

return (0);

}

4) Explain dynamic memory allocation & de-allocation by built-in functions 10m

Ans:

Memory is allocated/de-allocated dynamically at run time as and when required. Dynamic memory management refers to manual memory management. This allows a programmer to obtain more memory when required and release it when not necessary.

In C there are 4 library functions defined under stdlib.h or alloc.h for the same

malloc( ) - Allocates a block of memory of specified size in bytes and return a pointer of type void which can be casted into pointer of any form

Syntax:

ptr = (cast-type*) malloc(byte-size)

Example for p is 2-d array:

p= malloc(sizeof(int)*rows*cols)

If p is cast type then one example

p = (int *)malloc(sizeof(int)*100);

calloc() – Contiguous allocation – Allocates multiple blocks of same size – requires two arguments

calloc(number_of_blocks, size_in_bytes_for_each_block)

ptr = (cast-type*)calloc(n, element-size);

ptr = (float*) calloc(25, sizeof(float));

realloc( ) : changes/reallocates the size of previously allocated space by malloc() or calloc()

Syntax:

ptr = realloc(ptr, newsize);

if size1 is allocated by malloc: ptr = (int*) malloc(size1 * sizeof(int));

then to rallocate for size2

ptr = realloc(ptr, size2);

free() – To deallocate the previously allocated space

Syntax/example:

free(ptr)

This statement frees the space allocated in the memory pointed by ptr.

5. Explain any 5 pre-processor directives with example. Write 1 example program for macros. 10m

Ans:

A pre-processor represents pre-compilation process. These directives are preceded with # ( and there is no semicolon at the end).

C has the special feature of pre-processor directives. The pre-processor processes the C source code before it passes to the compiler. Pre-processor directives are executed before the C source code passes through the compiler.

Example of two pre-processor directives:

i) #include

This pre-processor is used to include another file. File name is written in angle brackets or

within double quotes.

#include <stdio.h>

#include “SORT.H”

File name enclosed within angle brackets are searched in standard directories. File name

enclosed within double quotes are searched first in the current directory and if not found

then it is searched in the standard directories.

ii) #define

#define directive is used to define the symbolic constant or macro name with macro

expression.

#define symconstant value

#define macroname macroexpression

Example

#define PI 3.141

Here the C pre-processor searches for the symbolic constant PI the source code and

substitutes 3.141 each time it is encountered.

As the function, a macro can have argument. The argument of the macro name is replaced

with actual argument of the macro name, which is encountered in the program.

Examples:

#define MAX(x,y) ( (x) > (y) ? (x) : (y) )

#define CUBE(x) (x)*(x)*(x)

iii) #ifdef

#ifdef preprocessor directives checks whether a macro is defined by #define. If yes, it executes

the code:

Example:

#ifdef PI

Printf(“PI symbolic constant is already defined\n”);

#endif

iV) #ifndef

#ifndef preprocessor directives checks whether a macro is not defined by #define. If yes, it

executes the code:

Example:

#ifndef PI

#define PI 3.14

#endif

V) #pragma

#pragma preprocessor directives schedules the execution of function before and after main()

function by clauses startup and exit:

Example:

#pragma startup func2

#pragma exit func1

Here func2() function will execute before main() function and func1() function will

execute after main() function. There is no need to call these function from main()

Example program for macros:

#include <stdio.h>

#define cube(x) x*x*x

int main()

{

printf(“%d”, cube(5+2))

return (0);

}

It gives the output 27 and not cube of 7 i.e. 343 because a macro is expanded in which way it is defined 5+2 * 5+2 * 5+2 and it gives 27. We can say it is blunder definition of macro. It should be defined as:

#define cube(x) (x)*(x)*(x)

Then it will give correct result

6. Explain push() and pop() operations of stack data structure. 10m

Stack is a LIFO (Last In First Out) data structure. Items can be inserted or deleted from one end(top) only

/*stack push() operation given in a function */

void push(int stack[], int item)

{

if(top==size-1)

print(“Stack is full-overflow.\n”);

else

{

top++;

stack[top]=item;

}

}

/*stack push() operation given in a function */

int pop(int stack[])

{

int d;

if(top==-1)

{

printf(“Stack is empty-underflow\n”);

return (NULL);

}

else

{

d=stack[top];

stack[top]=NULL;

top--;

return (d);

}

}

7 a) What do you mean by a linked list? Define structure of a linked list. 5M

Ans:

A linked list is a dynamic data structure where member of a structure is pointing to structure itself. It is also known as self referential structure.

New nodes can be added as and when required allocating the memory at run time. It requires extra space for address of the linked/next node:

| data | next---|---->| data | next---|---->| data | next---|----> NULL

#structure definition of a linked list

struct LIST

{

int data;

struct LIST *next;

};

typedef struct LIST node;

7 b) Explain primitive data types & derived data types. 5m

Ans:

A data type is a classification of data, which can store a specific type of information.

Primitive data types are primary, fundamental or predefined types of data, which are supported by the programming language. In C primitive data types are:

• char

• int

• float

• double

Programmers can use these data types when creating variables in their programs. For example, a programmer may create a variable called marks and define it as a int data type type.

Examples:

int marks;

double num = 0.00;

char c;

float sum;

Derived data types are non-primitive data types or composed data types from primary data types. Non-primitive data types are not defined by the programming language, but are instead created by the programmer. Arrays, pointers, structures are examples of derived data type.

Examples of derived/non-primitive data types:

int a[10]; /* array of 10 integers */

struct student

{

int roll;

char name[20];

int marks;

};

struct student s1,s2; /* s1 and s2 are structure variables or objects */

int *p; /* p is pointer variable to keep address of integer data */

8. Write a C program to count frequency of vowels & total number of consonants in a sentence (given by user) 10m

Ans:

/* to count frequency of vowels and total count of consonants */

#include <stdio.h>

#include <ctype.h>

int main()

{

char sent[50],c;

int x,a,e,i,o,u,conso;

printf("Enter sentence : ");

scanf(" %[^\n]",sent); /* to read string with blanks */

a=e=i=o=u=conso=0;

for(x=0;sent[x]!='\0';x++)

{

if(isalpha(sent[x])) /* checks alphabets only */

{

c=tolower(sent[x]);

if(c=='a') a++;

else if(c=='e') e++;

else if(c=='i') i++;

else if(c=='o') o++;

else if(c=='u') u++;

else conso++;

}

}

printf("a=%d,e=%d,i=%d,o=%d,u=%d,consonants=%d\n",a,e,i,o,u,conso);

return (0);

}

Expected output:

Enter sentence : you are a good boy

a=2,e=1,i=0,o=4,u=1,consonants=6

Solution of IAT-2(April 18)

Solution/Model Answer

PCDS-17PCD23 - IAT-2 (2^nd sem I & J Section)

Dr. P. N. Singh, Professor(CSE)

1.

a. Write a C Program to check whether a string (with space) is palindrome or not without using built-in functions. 5 M

Ans:

/* To check a string(with space) whether it is palindrome

without using built-in function*/

#include <stdio.h>

int main()

{

char str[50];

int x,y,len=0,palin=1;

printf("Enter string : ");

while((str[len]=getchar())!='\n')

len++;

str[len]='\0'; /* last character NULL */

y=len-1; /* coming before last character */

for(x=0;str[x]!='\0';x++,y--)

if(str[x]!=str[y])

{

palin=0;

break;

}

if(palin)

printf("Yes, \"%s\" is a palindrom\n",str);

else

printf("No, \"%s\" is not a palindrome\n",str);

return (0);

}

b. Write a C Program to find GCD of 2 numbers given by user using recursion. 5 M

Ans:

/* GCD of 2 numbers using recursive function*/

#include <stdio.h>

int GCD(int dividend,int divider)

{

int rem=dividend%divider;

if(rem==0)

return (divider);

else

return GCD(divider, rem);

}

main()

{

int n1,n2;

printf("Enter two numbers : ");

scanf("%d%d",&n1,&n2);

printf("GCD = %d\n",GCD(n1,n2));

return (0);

}

2. Write a C program to find sum and average of marks for 50 students in 6 papers each using 2-d array.

Ans:

/*sum and average of marks */

#include <stdio.h>

int main()

{

int marks[50][6],sum[50],x,y;

float avg[50];

for(x=0;x<50;x++)

{

sum[x]=0;

for(y=0;y<6;y++)

{

printf("Enter marks for student %d paper %d : ", x+1,y+1);

scanf("%d",&marks[x][y]);

sum[x]+=marks[x][y]; /* sum of marks */

}

avg[x]=sum[x]/6.00; /* average of marks for each student*/

}

printf("student p1 p2 p3 p4 p5 p6 sum average\n");

for(x=0;x<5;x++)

{

printf("%d.",x+1);

for(y=0;y<3;y++)

printf("%5d",marks[x][y]);

printf("%6d%7.2f\n",sum[x],avg[x]);

}

return (0);

}

3.

a. Describe string handling functions strlen(), strcpy(), strcat() and strcmp() 5M

Ans:

Header file for all string handling functions is string.h

strlen(str) – returns length of string in number of characters

example:

printf(“%d”,strlen(“PARAS”))

output : 5

strcpy(str1,str2) – Copies str2 to variable str1

example:

char name1[], name2[]=”ramaiyah”;

strcpy(name1,name2); /* copies name2 to name 1 */

strcat(str1, str2) – Concatenates(appends) str2 ton str1 at the end

example:

char name[]=”Roma”

char surname[]=”Ritambhara”

strcat(name,surname);

printf(“%s”, name);

Output: Roma Ritambhara

strcmp( str1, str2) – Compares two string and returns:

0 if both strings are identical

else returns difference based on ASCII value of first mismatch

printf(“%d”, strcmp(“SINGH”, “SINHA”);

output: - 1

b. Write a C program to check whether a number is prime or not. 5M

Ans:

/* to check a number whether it is prime or not */

#include <stdio.h>

#include <math.h>

int main()

{

int n,d,prime=1;

printf("Enter number : ");

scanf("%d",&n);

for(d=2;d<=sqrt(n);d++)

if(n%d==0)

{

prime=0;

break;

}

if(prime)

printf("Yes, %d is a prime number\n",n);

else

printf("No, %d is not prime number\n",n);

return (0);

}

4. Explain storage class extern, auto, static and register with examples. 10M

Ans:

The storage class specifies the portion of the program within which the variables are recognized. variables can be categorized by storage class as well as data type. Storage class refers to the permanence of a variable and its scope within the program, that is, the portion of the program over which the variable is recognized.

extern (external variables): They are global variables, known to all the functions of the program from point of definition. Hence, they usually span more than one functions, and often an entire program. Variables defined outside of the program are by default of extern storage class.

int global = 200;

int fullmarks = 100; /*external storage class variable */

main( )

{

......

}

auto (Automatic variables): They are local variables, available to the function in which it is declared. Their scope is confined to that function only. Variables declared within a function are by default of auto storage class.

auto int x,y,z;

int num; /* num is also interpreted as auto storage class

static (Static variable): Static variables have the same scope as automatic variables, i.e. they are local to the functions in which they are defined. Unlike automatic variables, however, static variables retain their values throughout the life of the program. As a result, if a function is called again, the static variables defined in the called function will retain their former values (They will not be reinitialized again. They are confined at the first initialization).

#include <stdio.h>

int func()

{

static int k = 0; /* by default also zero */

k++;

return (k);

}

int main()

{

int x, sum=0;

for(x=1;x<=5;x++)

sum+=func();

print(“sum = %d\n”, sum);

return (0);

}

register (Register variables) : Registers are special storage area within a computer’s central processing unit (In-built memory with CPU). The actual arithmetic and logical operations that comprise a program are carried out within this registers. The execution time can be reduced considerably if certain values can be stored within these registers rather than in computer’s memory.

The register variables are local to the function in which they are declared. The address of operator cannot ‘&’ cannot be applied to register variables.

register int x, y, z;

5. What is Bubble Sort? Implement Bubble sort for array of integers. 10M

Ans:

Bubble sort: Bubble sort is a sorting techniques to sort the items either in ascending or descending order. In Bubble sort adjacent elements are compared for swapping purpose. 1^st element is compared with second, 2^nd with 3^rd, 3^rd with 4^th and so on. In each pass the “heaviest” element sinks down and “lighter” elements “bubble” up.

/* program for Bubble sort */

#include <stdio.h>

int main()

{

int num[10],x,y,temp;

/* Accept values */

for(x=0;x<10;x++)

{

printf("Enter value %d:",x+1);

scanf("%d",&num[x]);

}

/* now sorting */

for(x=1;x<9;x++)

for(y=0;y<=10-x;y++)

if(num[y] > num[y+1])

{

temp=num[y];

num[y]=num[y+1];

num[y+1]=temp;

}

printf("\nSorted value:\n");

for(x=0;x<10;x++)

printf("%7d",num[x]);

return (0);

}

6. Implement Binary Search by a C program for initialized sorted array. 10M

Ans:

/* Binary search for sorted array */

#include <stdio.h>

int main()

{

int a[11]={20,24,26,37,48,59,67,77,88,99,111};

int x, skey,first,last,mid,found=0;

printf("The Sorted Array\n");

for(x=0;x<10;x++)

printf("%5d", a[x]);

printf("Enter item to search : ");

scanf("%d", &skey);

first=0; last=10;

while(first <= last && !found)

{

mid=(first+last)/2;

if(a[mid] > skey) last = mid-1;

else if(a[mid] < skey) first = mid+1;

else found=1;

}

if(found) printf("Found at %dth position\n", mid+1);

else printf("Not found\n");

return (0);

}

7.

a. Define structure. How structure members are accessed using dot (.) operator? 5M

Ans:

Structure is a data structure whose individual elements can differ in type. It may contain integer elements, character elements, pointers, arrays and even other structures can also be included as elements within a structure. struct is keyword to define a structure.

struct tag { type member1;

type member2;

type member3; ...... type member n;};

New structure type variables can be declared as follows:

struct tag var1, var2, var3, ....... varn;

Example :

struct library {

char b_name[30];

char author[30];

int price;

};

Now structure variables:

struct library book1, book2, book3;

It is allowed to combine both the template declaration and variable declaration in statement:

struct library {

char b_name[30];

char author[30];

int price;

} book1, book2, book3;

The link between a member and a variable is established using the member operator . (dot operator) or ->

Giving values to members:

book1.price = 76;

by scanf function:

scanf (“%d”,&book1.price);

b. How structure variables are passed as a parameter to a function? Write with example.

5M

Ans:

Passing structure to a function - There are three methods:

1) To pass each member of the structure as an actual arguments of the function call. It is unmanageable and inefficient when structure size is big.

2) To pass a copy of the entire structure to the called function. All compilers do not support this method. Changes to structure members in called function have no effect to calling function. Again we have it has to return entire copy of the changed structure to the calling function.

3) Address of the structure is passed and structure elements can be accessed indirectly. It is more effective method.

To send a copy of the structure:

function name ( structure variable name )

The called function takes the following form

data type function name ( structure type structure name )

{

..... ;

.....;

return (expression);

}

When a function returns a structure. It must be assigned to a structure of identical type in the calling function

8. Implement array of structure of students by a C program with fields roll, name and marks and to get data and sort array of structure based on marks in descending order. 5M

Ans:

/*sorting array of structure - based on marks in descending order*/

#include <stdio.h>

struct student

{

int roll;

char name[20];

int marks;

}s[1000]; /* array of structure */

int main()

{

int n,x,y;

struct student temp;

printf("How many students : ");

scanf("%d",&n);

for(x=0;x<n;x++)

{

printf("Enter roll, name and marks for student %d : ", x+1);

scanf("%d%s%d",&s[x].roll,s[x].name,&s[x].marks);

}

/*now sorting */

for(x=0;x<n-1;x++)

for(y=0;y<n-x-1;y++)

if(s[y].marks < s[y+1].marks)

{

temp=s[y];

s[y]=s[y+1];

s[y+1]=temp;

}

printf("roll name marks:\n");

for(x=0;x<n;x++)

printf("%5d%20s%5d\n",s[x].roll,s[x].name,s[x].marks);

return (0);

}

----------------- Think like a person of action; act like a person of thought.------------------

Solution of IAT-1 (March 2018)

Solution/Model Answer of IAT-1 (March 2018)

Programming in C & data Structure – 17PCD23

II sem – All

Dr. P. N. Singh, Professor(CSE)

1.

a. What is an identifier? What are rules to construct identifier? Classify following as valid/invalid

identifier.

num1, $num1, a_2, for, 1st_paper_marks. 06

Ans:

Identifiers - Names of variables, function, or arrays are identifiers.

Rules to construct identifier:

è They may contain A-Z, a-z, and _ (underscore) (no blanks)

è An identifier name but must be started with an alphabet or _ (specific purposes)

è Maximum length of name of identifier should be 31 characters (ANSI C standards) however in newer versions length of identifier name may be more.

è Keywords & compiler constants should not be identifier name

Valid identifiers: num1, a_2

Invalid identifiers: $num1, for, 1^st_paper_marks

b. Explain any 4 types of operators in C. 04

Ans:

Arithmetic Operators + (addition)

- (subtraction)

* (multiplication)

/ (division)

% (modulus)

Relational Operators < (less than)

<= (less than or equal to)

> (greater than)

>= (greater than or equal to)

==(equal to)

!=(not equal to)

Logical Operators && (and)

|| (or)

! (Not)

Assignment Operator =, +=, -=, */, /=, %=

2. What is an Algorithm? Write algorithm for the following i) To find area of triangle by given 3 sides ii) To check given number is Palindrome or not.

Ans:

Algorithm: An algorithm is step-by-step ( in the sequence ) procedure/ formula to get the solution of a task. Number of steps must be finite. Criteria of an algorithm to reduce the complexity of the solution.

i. Algorithm to find area of a triangle by given 3 sides

Step 1. Start

Step 2. Input sides a,b & c

Step 3. s=(a+b+c)/2

Step 4. If s <= a OR s <= b OR s <= c then

4.1 Print ‘Wrong measurement of triangle’

Step 5. Else

5.1 area=sqrt(s*(s-a)*(s-b)*(s-c))

5.2 Print area

Step 6. Endif

Step 7. End.

ii. Algorithm to check given number is palindrome or not

Step 1. Start

Step 2. Input num

Step 3. Temp=num

Step4. REV=0

Step 5. While temp <> 0

5.1 Rem=temp MOD 10

5.2 Rev=Rev*10+Rem

5.3 Temp=(integer)Temp/10

Step 6. Endwhile

Step 7. If rev = num then

7.1 Print “Number is palindrome”

Step 8. Else

8.1 Print “Number is not palindrome”

Step 9. Endif

Step10. End.

3.

a. With Syntax and example explain printf() and scanf() functions. 06

Ans:

printf() – Library function for formatted output:

Output data can be written on to a standard output device using the library function printf(). The printf statement provides certain features that can be effectively exploited to control the alignment and spacing of printouts on the terminals. The general form of printf statement is:

printf (“control string”, arg1,arg2, ........., argn);

Control string of printf function consists of three types of item :

· Character that will be printed on the screen as they appear.

· Format specification that define the output format for display of each item.

· Escape sequence characters such as \n,\t, and \b.

scanf() – Library function for formatted input

Formatted input refers to an input data that has been arranged in a particular format. Input data can be entered into the computer from a standard input device by means of the C library function scanf. In general terms, scanf function is written as

scanf (“control string”, &arg1, &arg2, ........., &argn);

The control string specifies the field format in which the data is to be entered and the arguments arg1,arg2.....,argn specify the address of locations where the data is stored. Actually arguments are pointers which indicate where the data items are stored in computer’s memory.

Control string contains field specification which direct the interpretation of input data. It may include:

· Field (or format) specification, consisting of the conversion character %, a data type character (or type specifier, and an optional number, specifying the field width.

· Blanks, tabs, or new lines.

· The arguments are written as variables or arrays, whose type match the corresponding character groups in the control string. Each variable name must be preceded by an ampersand (&). Array names should not begin with an ampersand.

b. Evaluate the expression: i) 100%20<=20-5+100%10-20==5>=1!=20

ii) a+=b*=c-=10 (Initial values, a=5,b=10 and c=15) 04

Ans:

(i) 100%20 <= 20-5+100%10-20 ==5>=1!=20

(Arithmetic operator has greater precedence than relational operator)

0 <= -5 == 5 >= 1 != 20

(Now associativity of relational operator is left to right)

0 == 5 >= 1 != 20

0 >= 1 != 20

0 != 20

1 Ans is 1 (True)

(ii) a+=b*=c-=10

(Associativity of assignment operator is right to left)

So, c - = 10 will be 5

b*=c will be 50

and a+=b will be 55

Finally Answer is: a = 55, b= 50 and c = 5

4.

a. Write a C program to calculate and display area of a rectangle. 5

Ans:

/* area of a rectangle */

#include <stdio.h>

int main()

{

float length, width, area;

printf(“Enter length & width of rectangle : “);

scanf(“%f%f”,&length, &width); /* input from keyboard*/

area=length*width;

printf(“Area = % .3 square unit\n”, area);

return (0);

}

Expected output:

Enter length and width: 5 4

Area = 20.000 square unit

b. Write a C program to calculate and display sum and average of 5 integers.

Ans:

#include <stdio.h>

int main()

{

int x,num, sum=0;

float avg;

for(x=1;x<=5;x++)

{

printf(“Enter number : “);

scanf(“%d”, &num);

sum+=num;

}

avg=sum/5.00;

printf(“sum = %d average = %f\n“, sum,avg);

return (0);

}

/* computing sum and average of 5 integers – without loop */

#include <stdio.h>

int main()

{

int n1,n2,n3,n4,n5,sum;

float avg;

printf(“Enter 5 integers : “);

scanf(“%d%d%d%d%d”, &n1,&n2,&n3,&n4,&n5);

sum=n1+n2+n3+n4+n5;

avg=sum/5.00;

printf(“sum = %d average = %f\n“, sum,avg);

return (0);

}

Expected output:

Enter 5 integers: 10 20 30 40 50

sum = 150 average = 30.000000

5.

a. Explain cascaded if else (else if ladder) and nested if statements with syntax and suitable example. 5

Ans:

Ladder of if ....else statement: for Multiple sets of conditions

if (expression/condition)

{statement1; statement2; ..... }

else if (expression/condition)

{statement1; statement2; ..... }

else if (expression/condition)

{statement1; statement2; ..... }

........

else

{statement1; statement2; ..... }

/* Example program to display division using if ladder*/

#include <stdio.h>

int main()

{

int marks;

printf(“Enter marks : “);

scanf(“%d”,&marks);

if(marks>=60)

printf(“First division\n”);

else

if(marks>=45) /* no surplus condition is required */

printf(“Second division\n”);

else

if(marks>=30)

printf(“Third division\n”);

else

printf(“Fail\n”);

return (0);

}

Nested if ...... else statement: if within if

if (expression/condition)

{ if (expression/condition)

{statement1; statement2; ..... }

else

{statement1; statement2; ..... }

}

else { if (expression/condition)

{statement1; statement2; ..... }

else

{statement1; statement2; ..... }

}

/* Example program to find maximum in 3 integers using nested if*/

#include <stdio.h>

int main()

{

int n1,n2,n3,max;

printf(“Enter 3 numbers : “);

scanf(“%d%d%d”,&n1,&n2,&n3);

if(n1 > n2)

if(n1 > n3)

max=n1;

else

max=n3;

else

if(n2 > n3)

max=n2;

else

max=n3;

print(“Maximum = %d\n”,max);

return (0);

}

b. Explain Structure of a C Program with Example 05

Ans:

Structure of C Program

/* Separate line comments –

------------ */

pre-processor directives /* header section */

global declarations

int main( ) /* main ( ) function section */

{

local variables to function main ;

statements associated with function main ;

………………….

return (0);

}

udf1( ) /* user defined functions */

{

local variables to user defined function udf1 ;

statements associated with udf1 ;

}

.

.

/* Example program to calculate simple interest */

#include <stdio.h>

int main( )

{

float p,r,t,si;

printf(“Enter principle, rate and time : “);

scanf(“%f%f%f”, &p, &r, &t);

si=p*r*t/100.00;

printf(“Simple interest = %f\n”, si);

return (0);

}

6. Explain switch case statement with syntax and example of a calculator program to do simple operations like addition, subtraction, multiplication and division. 10

switch statement:

switch (expression)

{

case condition1

statement1;

statement2;

......

break;

case condition2

statement1;

statement2;

.......

break;

.....

default:

statement1;

statement2;

.......

}

/* Arithmetic operation by switch */

int main( )

{

float n1,n2,result;

int choice;

printf(“Enter 2 numbers : “);

scanf(“%f%f”, &n1, &n2);

printf(“1. Addition 2. Subtraction 3. Multiplication 4. Division:\n”);

printf(“Enter your choice number : “);

scanf(“%d”, &choice);

switch(choice)

{

case 1 : result = n1+n2;

break;

case 2 : result = n1-n2;

break;

case 3 : result = n1*n2;

break;

case 4 : if(n2 == 0)

{ printf(“divide error!!!\n”); return (99); }

else

result = n1/n2;

break;

default: printf(“Wrong choice!\n”);

}

printf(“Result = %f\n”, result);

return (0);

}

Expected Output:

Enter 2 numbers : 50 25

1. Addition 2. Subtraction 3. Multiplication 4. Division:

Enter your choice number : 4

Result = 2.000000

7. Write a C program to find roots of a quadratic equation of the form ax²+bx+c=0, where a, b and c are coefficients. Explain the output for all possible cases. 10

Ans:

/* to find roots of quadratic equation */

#include <stdio.h>

#include <math.h>

main()

{

float a,b,c,d,r1,r2, rpart,ipart;

printf("Enter values of a, b and c : ");

scanf("%f%f%f",&a,&b,&c);

if(a==0) { printf(“The equation is not quadratic\n”); return (99); }

d=b*b-4*a*c;

if(d==0)

{

r1=r2=-b/(2.0*a);

printf(“Roots are real and equal: %f\n”,r1);

}

else

if(d > 0)

{

r1=(b+sqrt(d))/(2*a);

r2=(b-sqrt(d))/(2*a);

printf("Roots are distinct : %.3f and %.3f\n",r1,r2);

}

else /* computing imaginary roots*/

{

rpart=-b/(2.0*a);

ipart=sqrt(-d)/(2.0*a);

printf(“Roots are imaginary:\n”);

printf(“ r1=%f+i*%f\n r2=%f-i*%f\n”,rpart,ipart,rpart,ipart);

}

return (0);

}

8.

a. Explain while loop with an example. 5

Ans:

while loop: while is a looping statement where statements are executed till the condition is satisfied/true.

Syntax:

while (condition)

{

statement1;

statement2;

......

}

Example:

/* while loop example to display number and message 5 times */

#include <stdio.h>

int main()

{

int x=1;

while(x<=5)

{

printf(“%d. %s\n”, x, “Kudi Punjaban Dil chura ke le gayee – Sona Sona”);

x++;

}

return (0);

}

Expected Output:

1. Kudi Punjaban Dil chura ke le gayee – Sona Sona

2. Kudi Punjaban Dil chura ke le gayee – Sona Sona

3. Kudi Punjaban Dil chura ke le gayee – Sona Sona

4. Kudi Punjaban Dil chura ke le gayee – Sona Sona

5. Kudi Punjaban Dil chura ke le gayee – Sona Sona

b. Write a program to find whether the given year is leap or not. (consider century year) 5

Ans:

/* to find whether the given year is leap year or not */

#include <stdio.h>

int main( )

{

int year;

printf(“Enter year : “);

scanf(“%d”, &year);

if((year%4==0 && year%100 != 0)|| year%400==0)

printf(“Yes, %d is leap year.\n”, year);

else

printf(“No, %d is not leap year.\n”, year);

return (0);

}

Expected Output:

Enter year: 2016

Yes, 2016 is leap year.

Again

Enter year: 1900

No, 1900 is not leap year.

Again

Enter year: 2000

Yes, 2000 is leap year

Solution to IAT-I

CMR

INSTITUTE OF

TECHNOLOGY

Solution/Model Answer of IAT-1 (March 2017)

Programming in C & data Structure – 15PCD23

II sem – All

Dr. P. N. Singh, Professor(CSE)

1. Explain Structure of a C Program. Write a program to calculate simple interest 10

Ans:

Structure of C Program

/* Separate line comments –

------------ */

pre-processor directives /* header section */

global declarations

int main( ) /* main ( ) function section */

{

local variables to function main ;

statements associated with function main ;

………………….

return (0);

}

udf1( ) /* user defined functions */

{

local variables to user defined function udf1 ;

statements associated with udf1 ;

}

.

.

/* program to calculate simple interest */

int main( )

{

float p,r,t,si;

printf(“Enter principle, rate and time : “);

scanf(“%f%f%f”, &p, &r, &t);

si=p*r*t/100.00;

printf(“Simple interest = %f\n”, si);

return (0);

}

2.

a. Define an operator? Explain with Example 6

C includes a large number of operators. Individual constants, variables, array elements and function references can be joined by various operation to form expressions. The data items that operators act upon are called operands.

Examples of some operators:

Arithmetic Operators + (addition) - (subtraction) * (multiplication)

/ (division) % (modulus)

unary operator - (minus) acts upon a single operand

( oh! C does not have an operator for exponentiation)

Relational Operators < (less than) <= (less than or equal to) > (greater than) >= (greater than or equal to)

equality operators = = (equal to) != (not equal to)

Logical Operators && (and) || (or)

unary operator ! negates the value of a logical operator

!(n<=10) - n is not less than or equal to 10

b. Describe data types in C? Explain the syntax for variable declaration and initialization.

4

Data type Description

int integer quantity

char single character

float (real) floating point number(i.e., a number containing a decimal point and/or an exponent

double double-precision floating-point number

(i.e., more significant figures, and an exponent which may be larger in magnitude.)

Syntax for variable declaration & initialization:

datatype variable;

int num;

float radius;

datatype variable = value;

int num=20;

float radius = 5.067;

3.

a. Define an Identifier? List the rules to construct an identifier? Give examples of valid and invalid identifier. 4

Ans:

Identifiers - Names of variables, function, or arrays are identifiers.

Rules:

è They may contain A-Z, a-z, and _ (underscore) (no blanks)

è An identifier name but must be started with an alphabet or _ (specific purposes)

è Maximum length of name of identifier should be 31 characters (ANSI C standards) however in newer versions length of identifier name may be more.

è Keywords & compiler constants should not be identifier name

Examples of valid identifiers: amount, order_no, marks1, stud[10], sort( )

Examples of invalid identifiers: 1stpaper, for, if, name of student

b. Explain different conditional decision making statements with syntax. 6

Ans:

if statement: .........

if (expression/condition)

{

statement1;

statement2;

...

}

if .... else statement:

if (expression/condition)

{ statement1;

statement2;

........

}

else

{ statement1;

statement2;

......

}

Ladder of if ....else statement:

if (expression/condition)

{statement1; statement2; ..... }

else if (expression/condition)

{statement1; statement2; ..... }

else if (expression/condition)

{statement1; statement2; ..... }

........

else

{statement1; statement2; ..... }

Nested if ...... else statement:

if (expression/condition)

{ if (expression/condition)

{statement1; statement2; ..... }

else

{statement1; statement2; ..... }

}

else { if (expression/condition)

{statement1; statement2; ..... }

else

{statement1; statement2; ..... }

}

switch statement:

switch (expression)

{

case condition1

statement1;

statement2;

......

break;

case condition2

statement1;

statement2;

.......

break;

.....

default:

statement1;

statement2;

.......

}

4.

a. Write a program to find greatest of the 3 numbers using nested if-else. 5

Ans:

/* program to find greatest in the 3 numbers using nested if-else */

#include <stdio.h>

int main( )

{

int n1, n2, n3,max;

printf(“Enter 3 numbers : “);

scanf(“%d%d%d”, &n1, &n2, &n3);

if(n1 > n2)

if(n1 > n3)

max=n1;

else

max=n3;

else

if (n2 > n3)

max=n2;

else

max=n3;

printf(“Greatest = %d\n”, max);

return (0);

}

b. Write a program to find whether the given year is leap or not. (consider century year) 5

Ans:

/* to find whether the given year is leap year or not */

#include <stdio.h>

int main( )

{

int year;

printf(“Enter year : “);

scanf(“%d”, &year);

if((year%4==0 && year%100 != 0)|| year%400==0)

printf(“Yes, %d is leap year.\n”, year);

else

printf(“No, %d is not leap year.\n”, year);

return (0);

}

5.

a. Differentiate between while and do-while loop. 6

Ans:

The while statement:

while (condition)

{

statement1;

statement2;

......

}

The do ..... while statement:

do

{

statement1;

statement2;

......

} while (condition);

è While is a pre-tested loop/entry controlled loop and do… while is post-tested loop

è Post-tested loop must execute at least once because condition is checked at the end of loop

b. Write a program to check whether the given number is even or odd. (Use conditional Operator) 4

Ans:

/* to check whether a given number is even or odd - using conditional operator*/

#include <stdio.h>

int main()

{

int n;

printf(“Enter number : “)

scanf(“%d”, &n);

printf(“Number is %s\n”, n%2 == 0 ? “ Even” : “Odd”);

return (0);

}

6.

a. Evaluate the following expression. 4

a=5, b=6, c=7

d= ++a * b –c;

e = a & b

f=100%20<=20-5+100%10-20= =5>=1!=20;

g=c-- *b+d;

Ans:

d = 6 * 6 – 7 = 29

e = 6 & 6 = 6 (by bit wise operator 110 & 110)

f = 1 (true, finally not equal to 20)

g = 7 * 6 + 29 = 71 ( post decrement of c after statement)

b. What will be value of x in following segments? 4

int a,b; float x; a=4; b=5; x=b/a;

int a,b; float x; a=4; b=5; x= (float) b/a;

Ans:

int a,b; float x; a=4; b=5; x=b/a;

x = 1.0 (integer values b/a is not casted)

int a,b; float x; a=4; b=5; x= (float) b/a;

x = 1.25 (b/a is casted)

c. What is difference between 7, 7.0, ‘7’, “7” ? 2

Ans:

7 Integer constant

7.0 floating point constant

‘7’ character constant

“7” string constant

7. Explain the syntax of switch case. Write a program to perform basic arithmetic operations like addition, subtraction, multiplication & division, using switch statement. (Error message should be displayed if number is divided by 0) 10

Ans:

/* Arithmetic operation by switch */

int main( )

{

float n1,n2,result;

int choice;

printf(“Enter 2 number : “);

scanf(“%f%f”, &n1, &n2);

printf(“1. Addition 2. Subtraction 3. Multiplication 4. Division:\n”);

printf(“Enter your choice number : “);

scanf(“%d”, &choice);

switch(choice)

{

case 1 : result = n1+n2;

break;

case 2 : result = n1-n2;

break;

case 3 : result = n1*n2;

break;

case 4 : if(n2 == 0)

{ printf(“divide error!!!\n”); return (99); }

else

result = n1/n2;

break;

default: printf(“Wrong choice!\n”);

}

printf(“Result = %f\n”, result);

return (0);

}

8.

a. Write a program and pseudo-code to check whether the given number is palindrome or not. 5

Ans:

Pseudo-code to check given number is palindrome or not

START

INPUT NUM

TEMP=NUM

REV=0

WHILE TEMP <> 0

REM=TEMP MOD 10

REV=REV*10+REM

TEMP=(INTEGER)TEMP/10

ENDWHILE

IF REV = NUM THEN

PRINT “NUMBER IS PALINDROME”

ELSE

PRINT “NUMBER IS NOT PALINDROME”

ENDIF

END.

/*Program to check given number is palindrome */

#include <stdio.h>

int main()

{

long int num,temp,rev,rem;

printf(“Enter Number : “);

scanf(“%ld”, &num);

temp=num;

rev=0;

while (temp !=0)

{

rem=temp%10;

rev=rev*10+rem;

temp/=10;

}

if(rev==num)

printf(“Yes, %ld is palindrome\n”, num);

else

printf(“No, %ld is not palindrome\n”, num);

return (0);

}

b. Write a program to print Fibonacci series up to n terms. 5

Ans:

/* to print Fibonacci series up to n terms */

#include <stdio.h>

int main( )

{

long int a=0,b=1,c;

int n,x;

printf(“How many numbers of Fibonacci series ( > 2) ? “);

scanf(“%d”, &n);

printf(“%7ld%7ld”, a,b);

for(x=3;x<=n;x++)

{

c=a+b;

printf(“%7ld”, c);

a=b;

b=c;

}

return (0);

}

Solution of IAT - 2

CMR

INSTITUTE OF

TECHNOLOGY

Solution/Model Answer of IAT-2 (May 2017)

Programming in C & data Structure – 15PCD23

II sem – G & F

Dr. P. N. Singh, Professor(CSE)

1. a) What is array? Explain the declaration and initialization of one and two dimensional arrays

with example. 10

Ans:

Array is collection of similar data types.

An array is an identifier that refers to the collection of data items which all have the same name. The individual data items are represented by their corresponding array elements. Element ranges from 0 to n-1 where n is total number of elements.

One-dimensional array

Declaration:

syntax: datatype arrayname[size];

examples: float height[50];

int batch[10];

char name[20];

Initialization:

int marks[5] = {76,45,67,87,92};

static int count[ ] = {1,2,3,4,5};

static char name[ ] = {‘S’, ‘I’, ‘N’, ‘G’, ‘H’};

Two-dimensional array

Declaration:

syntax: type arrayname[rowsize][columnsize];

examples: static int stud[16][5];

Initialization:

int marks[3][3] = {

{26,57,66},

{56,77,48},

{76,54,82}

};

static int marks[3][3] = { {0},{0},{0}};

Here first element of each row is explicitly initialized to zero while other elements

are automatically initialized to zero.

2 a) Write a program to implement the strcpy function. 4

Ans:

strcpy(strvar, strval) function is used to copy string value to string variable. Related header file is string.h

/*Program to implement strcpy() function */

#include <stdio.h>

#include <string.h>

int main()

{

char str1[30], str2[30];

printf(“Enter string : “);

scanf(“%s”, str1);

strcpy(str2,str1); /* to copy str1 to str2 */

printf(“copied string is %s\n”,str2);

return (0);

}

2b) Explain any 4 string manipulation functions with examples 6

Ans:

i. strlen( ) : Returns length of string in bytes.

Syntax:

int strlen(str);

Example:

printf(“Length of string = %d\n”, strlen(“SINGH”));

output will be 5

ii. strcpy( ): copies string

Syntax:

void strcpy(stringvar, stringval);

Example:

strcpy(name,”SINGH”);

SINGH string is copied to string variable name.

iii. strcat( ): concatenates 2^nd string to 1^st string

Syntax:

void strcat(name, surname);

Example:

strcpy(name,”VIKRAM”);

strcpy(surname,”SINGH”);

SINGH will be appended to string variable name and now name is VIKRAMSINGH

iv. strrev( ): reverses string

Syntax:

void strrev(string);

Example:

strcpy(name,”VIKRAM”);

strrev(name);

Now name is MARKIV

3a) Describe the different methods of passing parameters to functions, with examples. 5

Ans:

Parameters can be passed by two ways:

i. Pass by value/variable

ii. Pass by address