palindromesolution

palindromesolution.java

class Solution {
  public static void main(String[] args) {
    String PString = "0 man, a plan, a canal: Panam0";
    String nonPString = "race a car";
    
    System.out.println("is PString a Palindrome? : " + isPalindrome(PString));
    System.out.println("is nonPString a Palindrome? : " + isPalindrome(nonPString));
  }
  
  public static boolean isPalindrome(String str) {
    int size = str.length();
    
    int left = 0;
    int right = size - 1;
    
    while (right >= left) {
      if (str.toLowerCase().charAt(right) == str.toLowerCase().charAt(left)) {
          right--;
          left++;
      } else if (!Character.isLetter(str.charAt(right))) {
          right--;
      } else if (!Character.isLetter(str.charAt(left))) {
          left++; 
      } else {
          return false; 
      }
    }
    
    return true;
  }
}