Palindrome Program in Java

 Palindrome number in java: A palindrome number is a number that is same after reverse. For example 545, 151, 34543, 343, 171, 48984 are the palindrome numbers. It can also be a string like LOL, MADAM etc.

Palindrome number algorithm

• Get the number to check for palindrome
• Hold the number in temporary variable
• Reverse the number
• Compare the temporary number with reversed number
• If both numbers are same, print "palindrome number"
• Else print "not palindrome number"

• Let's see the palindrome program in java. In this java program, we will get a number variable and check whether number is palindrome or not.

  1. class PalindromeExample{  
  2.  public static void main(String args[]){  
  3.   int r,sum=0,temp;    
  4.   int n=454;//It is the number variable to be checked for palindrome  
  5.   
  6.   temp=n;    
  7.   while(n>0){    
  8.    r=n%10;  //getting remainder  
  9.    sum=(sum*10)+r;    
  10.    n=n/10;    
  11.   }    
  12.   if(temp==sum)    
  13.    System.out.println("palindrome number ");    
  14.   else    
  15.    System.out.println("not palindrome");    
  16. }  
  17. }  

  Output:

  palindrome  number
  

  Palindrome Program in Java (Another way)

  You can also use a method where number or string is not predefined. Here, user has to put the number or string as input to check if the number/string is palindrome.Let's see the palindrome program in java. In this java program, we will get a number variable and check whether number is palindrome or not.

  1. class PalindromeExample{  
  2.  public static void main(String args[]){  
  3.   int r,sum=0,temp;    
  4.   int n=454;//It is the number variable to be checked for palindrome  
  5.   
  6.   temp=n;    
  7.   while(n>0){    
  8.    r=n%10;  //getting remainder  
  9.    sum=(sum*10)+r;    
  10.    n=n/10;    
  11.   }    
  12.   if(temp==sum)    
  13.    System.out.println("palindrome number ");    
  14.   else    
  15.    System.out.println("not palindrome");    
  16. }  
  17. }  

  Output:

  palindrome  number
  

  Palindrome Program in Java (Another way)

  You can also use a method where number or string is not predefined. Here, user has to put the number or string as input to check if the number/string is palindrome.

  1. import java.util.*;   
  2. class PalindromeExample2  
  3. {  
  4.    public static void main(String args[])  
  5.    {  
  6.       String original, reverse = ""; // Objects of String class  
  7.       Scanner in = new Scanner(System.in);   
  8.       System.out.println("Enter a string/number to check if it is a palindrome");  
  9.       original = in.nextLine();   
  10.       int length = original.length();   
  11.       for ( int i = length - 1; i >= 0; i-- )  
  12.          reverse = reverse + original.charAt(i);  
  13.       if (original.equals(reverse))  
  14.          System.out.println("Entered string/number is a palindrome.");  
  15.       else  
  16.          System.out.println("Entered string/number isn't a palindrome.");   
  17.    }  
  18. }  

  Output: