Is the string a palindrome?

One of classic problem - easy to solve.

Problem

Given a string, need to check if this string a palindrome?

Solution

The key is to create two methods - using "one method - one responsibility approach": to validate the String and to reverse the String.

Solution 1

public class Solution {
    private static boolean isPalindrome(String str) {
 
        if (str.equals(reverseString(str)){
           return true;
        }
        return false;
    }

   private static String reverseString(String str){
        return (new StringBuilder(str)).reverse().toString();
   }
}

Memory O(n)Steps: O(n) - linear