check for palindrome recursion code example

Example 1: Java program to check palindrome string using recursion

import java.util.Scanner;
public class RecursivePalindromeJava 
{
   // to check if string is palindrome using recursion
   public static boolean checkPalindrome(String str)
   {
      if(str.length() == 0 || str.length() == 1)
         return true; 
      if(str.charAt(0) == str.charAt(str.length() - 1))
         return checkPalindrome(str.substring(1, str.length() - 1));
      return false;
   }
   public static void main(String[]args)
   {
      Scanner sc = new Scanner(System.in);
      System.out.println("Please enter a string : ");
      String strInput = sc.nextLine();
      if(checkPalindrome(strInput))
      {
         System.out.println(strInput + " is palindrome");
      }
      else
      {
         System.out.println(strInput + " not a palindrome");
      }
      sc.close();
   }
}

Example 2: reads the string in then determines if the string is a palindrome.

#include <iostream>
using namespace std;
 
// Recursive function to check if str[low..high] is a palindrome or not
bool isPalindrome(string str, int low, int high)
{
    // base case
    if (low >= high)
        return true;
 
    // return false if mismatch happens
    if (str[low] != str[high])
        return false;
 
    // move to next the pair
    return isPalindrome(str, low + 1, high - 1);
}
 
int main()
{
    string str = "XYBYBYX";
    int len = str.length();
 
    if (isPalindrome(str, 0, len - 1))
        cout << "Palindrome";
    else
        cout << "Not Palindrome";
 
    return 0;
}

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