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Check palindrome recursively

Check palindrome recursively

Monday, November 13, 2023 ⁃ Difficulty: Intermediate

Objective

Create a Java program that implements a recursive function to check whether a string is a palindrome or not. A palindrome is a string that reads the same backward as forward, like the word radar.

Instructions

From the main function (main) of the program, prompt the user to input a text string.
Implement a recursive function called isPalindrome that takes the input string and checks if it is a palindrome.
The isPalindrome function should return true if the string is a palindrome and false otherwise.
Print a message on the screen indicating whether the string is a palindrome or not.

Input

radar

Output

true

Solution

CheckPalindromeRecursively.java

import java.util.Scanner;

public class CheckPalindromeRecursively {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.println("Enter a string: ");
        String text = input.nextLine();
        input.close();

        boolean isPalindrome = isPalindrome(text);
        System.out.println(isPalindrome);
    }

    public static boolean isPalindrome(String text) {
        if (text.length() <= 1) {
            return true;
        } else {
            if (text.charAt(0) != text.charAt(text.length() - 1)) {
                return false;
            } else {
                return isPalindrome(text.substring(1, text.length() - 1));
            }
        }
    }
}

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