JAVA Logical Program

Reverse Number 

public class ReverseNumber { 

public static void main(String args [ ])

 {

int number=26426;

int temp,reverse=0; 

int a=number; 

//Original number 

System.out.println("Given number is = "+a); 

while(number>0) 

{ 

temp=number%10; 

reverse=reverse*10+temp; 

number=number/10; 

} 

System.out.println("The reverse of "+a+" is = "+reverse); 

// by StringBuffer method 

// StringBuffer sb=new StringBuffer(String.valueOf(a)); 

// StringBuffer b = sb.reverse(); 

// System.out.println(b); 

} 

Given number is = 26426 

The reverse of 26426 is = 6246 

Reverse String 

public class ReverseString { 

public static void main(String args [ ]) 

{ 

String str="The Sun is brightest star in universe"; 

String reverse=""; 

//String to array conversion 

char[ ] a = str.toCharArray( );

//String to array conversion 

System.out.println("Given String is = "+str); 

//length of string 

int length=str.length(); 

for(int i=length-1;i>=0;i--) 

{ 

reverse=reverse+a[i];

 } 

//reverse string 

System.out.println("The reverse is = "+reverse); 

/* 

//By String Buffer method 

StringBuffer sb=new StringBuffer(str); 

StringBuffer b = sb.reverse(); 

System.out.println(b); 

*/

 } 

} 

Given String is = The Sun is brightest star in universe 

The reverse is = esrevinu ni rats tsethgirb si nuS ehT 

/* 01 -  Reverse a number -----------------

int n =12345, rev=0;

while(n!=0){

int r = n%10;

n = n/10;

rev = rev*10+r;

}

System.out.println("Reversed = "+rev);  

*/

/* 02 -  Reverse string by Words  ----------

String s = "life is beautiful enjoy it";

String[] parts = s.split(" ");

for(int i=parts.length-1;i>=0;i--)

//for(int i=0;i<=parts.length;i--)

System.out.print(parts[i]+" ");

*/

/* 03 -  Reverse string by character  ------------

String s = "life is beautiful enjoy it";

for(int i=s.length()-1;i>=0;i--)

System.out.print(s.charAt(i));

*/

/* 04 -  Convert First Character of String to UpperCase  --------------

String s = "life is beautiful enjoy it";

String[] parts = s.split(" ");

for(int i=0;i<parts.length;i++){

char[] ch = parts[i].toCharArray();

for(int j=0;j<ch.length;j++){

ch[0] = Character.toUpperCase(ch[0]);

System.out.print(ch[j]);

}

System.out.print(" ");

}

*/

/* 05 -  Count of Characters in String (Incomplete)-----------------------

Create an array of size 256 i.e. ASCII_SIZE 

String s = "abbcccdddd";

char[] ch = s.toCharArray();

for(int i=0;i<ch.length;i++){

int counter=0;

char c=s.charAt(i);

for(int j=0;j<s.length();j++){

if(c==ch[j]){

counter++;

ch[j] = '\u0000'; // OR ch[j] = 0; 

}

}

if(counter>0)

System.out.println(c+" "+counter);

}

*/

Fibonacci Series 

public class FibonacciSeries { 

public static void main(String args [ ]) 

{ 

int num1=1; 

int num2=1; 

int count=10; 

int num = 0; 

//First two number 

System.out.print(num1+" "+num2+" "); 

for (int i=2;i<=count;i++) 

{ 

num=num1+num2; 

num1=num2; 

num2=num; 

System.out.print(num +" "); 

} 

} 

} 

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