Check whether String is palindrome using recursion

java program to check palindrome string using recursion

Author: Shubhamkr36

java program to check palindrome string using recursion

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+package beginnersbook.com;
+import java.util.Scanner;
+class PalindromeCheck
+{
+    //My Method to check
+    public static boolean isPal(String s)
+    {   // if length is 0 or 1 then String is palindrome
+        if(s.length() == 0 || s.length() == 1)
+            return true; 
+        if(s.charAt(0) == s.charAt(s.length()-1))
+        /* check for first and last char of String:
+         * if they are same then do the same thing for a substring
+         * with first and last char removed. and carry on this
+         * until you string completes or condition fails
+         * Function calling itself: Recursion
+         */
+        return isPal(s.substring(1, s.length()-1));
+
+        /* If program control reaches to this statement it means
+         * the String is not palindrome hence return false.
+         */
+        return false;
+    }
+
+    public static void main(String[]args)
+    {
+    	//For capturing user input
+        Scanner scanner = new Scanner(System.in);
+        System.out.println("Enter the String for check:");
+        String string = scanner.nextLine();
+        /* If function returns true then the string is
+         * palindrome else not
+         */
+        if(isPal(string))
+            System.out.println(string + " is a palindrome");
+        else
+            System.out.println(string + " is not a palindrome");
+    }
+}