C++: Practicing programs

C++ programs

#include <iostream>
using namespace std;
 
// Function prototype (declaration)
int add(int, int);
 
int main()
{
    int num1, num2, sum;
    cout<<"Enters two numbers to add: ";
    cin >> num1 >> num2;
 
    // Function call
    sum = add(num1, num2);
    cout << "Sum = " << sum;
    return 0;
}
 
// Function definition
int add(int a, int b)
{
    int add;
    add = a + b;
 
    // Return statement
    return add;
}
#include <iostream>
using namespace std;
 
void prime(int n);
 
int main()
{
    int num;
    cout << "Enter a positive integer to check: ";
    cin >> num;
    
    // Argument num is passed to the function prime()
    prime(num);
    return 0;
}
 
// There is no return value to calling function. Hence, return type of function is void. */
void prime(int n)
{
    int i, flag = 0;
    for (i = 2; i <= n/2; ++i)
    {
        if (n%i == 0)
        {
            flag = 1;
            break;
        }
    }
 
    if (flag == 1)
    {
        cout << n << " is not a prime number.";
    }
    else {
        cout << n << " is a prime number.";
    }
}
#include <iostream>
using namespace std;
 
int absolute(int);
float absolute(float);
 
int main() {
    int a = -5;
    float b = 5.5;
    
    cout << "Absolute value of " << a << " = " << absolute(a) << endl;
    cout << "Absolute value of " << b << " = " << absolute(b);
    return 0;
}
 
int absolute(int var) {
     if (var < 0)
         var = -var;
    return var;
}
 
float absolute(float var){
    if (var < 0.0)
        var = -var;
    return var;
}
#include <iostream>
using namespace std;
 
void display(char = '*', int = 1);
 
int main()
{
    cout << "No argument passed:\n";
    display();
    
    cout << "\nFirst argument passed:\n";
    display('#');
    
    cout << "\nBoth argument passed:\n";
    display('$', 5);
 
    return 0;
}
 
void display(char c, int n)
{
    for(int i = 1; i <= n; ++i)
    {
        cout << c;
    }
    cout << endl;
}
#include <iostream>
using namespace std;
 
int factorial(int);
 
int main() 
{
    int n;
    cout<<"Enter a number to find factorial: ";
    cin >> n;
    cout << "Factorial of " << n <<" = " << factorial(n);
    return 0;
}
 
int factorial(int n) 
{
    if (n > 1) 
    {
        return n*factorial(n-1);
    }
    else 
    {
        return 1;
    }
}
#include <iostream>
using namespace std;
 
int main() 
{
    int numbers[5], sum = 0;
    cout << "Enter 5 numbers: ";
    
    //  Storing 5 number entered by user in an array
    //  Finding the sum of numbers entered
    for (int i = 0; i < 5; ++i) 
    {
        cin >> numbers[i];
        sum += numbers[i];
    }
    
    cout << "Sum = " << sum << endl;  
    
    return 0;
}
#include <iostream>
using namespace std;
 
const int CITY = 2;
const int WEEK = 7;
 
int main()
{
    int temperature[CITY][WEEK];
 
    cout << "Enter all temperature for a week of first city and then second city. \n";
 
    // Inserting the values into the temperature array
    for (int i = 0; i < CITY; ++i)
    {
        for(int j = 0; j < WEEK; ++j)
        {
            cout << "City " << i + 1 << ", Day " << j + 1 << " : ";
            cin >> temperature[i][j];
        }
    }
 
    cout << "\n\nDisplaying Values:\n";
 
    // Accessing the values from the temperature array
    for (int i = 0; i < CITY; ++i)
    {
        for(int j = 0; j < WEEK; ++j)
        {
            cout << "City " << i + 1 << ", Day " << j + 1 << " = " << temperature[i][j] << endl;
        }
    }
 
    return 0;
}
#include <iostream>
using namespace std;
 
int main()
{
    // This array can store upto 12 elements (2x3x2)
    int test[2][3][2];
 
    cout << "Enter 12 values: \n";
    
    // Inserting the values into the test array
    // using 3 nested for loops.
    for(int i = 0; i < 2; ++i)
    {
        for (int j = 0; j < 3; ++j)
        {
            for(int k = 0; k < 2; ++k )
            {
                cin >> test[i][j][k];
            }
        }
    }
 
    cout<<"\nDisplaying Value stored:"<<endl;
 
    // Displaying the values with proper index.
    for(int i = 0; i < 2; ++i)
    {
        for (int j = 0; j < 3; ++j)
        {
            for(int k = 0; k < 2; ++k)
            {
                cout << "test[" << i << "][" << j << "][" << k << "] = " << test[i][j][k] << endl;
            }
        }
    }
 
    return 0;
}
#include <iostream>
using namespace std;
 
void display(int n[3][2]);
 
int main()
{
    int num[3][2] = {
        {3, 4},
        {9, 5},
        {7, 1}
 
    };
    display(num);
 
    return 0;
}
 
void display(int n[3][2])
{
 
    cout << "Displaying Values: " << endl;
    for(int i = 0;  i < 3; ++i)
    {
        for(int j = 0; j < 2; ++j)
        {
            cout << n[i][j] << " ";
        }
    }
}
#include <iostream>
using namespace std;
 
int main()
{
    char str[100];
    cout << "Enter a string: ";
    cin.get(str, 100);
 
    cout << "You entered: " << str << endl;
    return 0;
}
#include <iostream>
 
using namespace std;
 
void display(char *);
void display(string);
 
int main()
{
    string str1;
    char str[100];
 
    cout << "Enter a string: ";
    getline(cin, str1);
 
    cout << "Enter another string: ";
    cin.get(str, 100, '\n');
 
    display(str1);
    display(str);
    return 0;
}
 
void display(char s[])
{
    cout << "Entered char array is: " << s << endl;
}
 
void display(string s)
{
    cout << "Entered string is: " << s << endl;
}