Styjun

public class Lab3Exercises {

public static void main(String[] args)
 Scanner s = new Scanner([System.in](https://System.in));
 System.out.println("Please enter a word to check if it is a palindrome");
 String myP = [s.next](https://s.next)();
 System.out.println(palindrome(myP));


public static boolean palindrome(String p)
 String myWord = p;
 String reverseWord = "";
 int i = 1;
 while (i < myWord.length())
 reverseWord = myWord.charAt(i) + myWord.substring(0, i) + myWord.substring((i + 1), myWord.length());
 i++;
 
 if (reverseWord.equals(myWord)) 
 return true;
 
 else
 return false; 
 

I checked and the reverseWord is the exact same as myWord yet it returns false everytime. I've tried hannah, racecar, etc. they all return false

Let’s start from the simpler examples.

• If p has length 1, for example s (a palindrome), you are setting reverseWord to the empty string. Since i starts from 1, it is not less than the length, so the loop does not run. Since the empty string is not equal to s, the method returns false.


• Input tt (another palindrome). You are running once through the loop, setting reverseWord to "t" + "t" + "" = "tt". The method correctly returns true in this case.


• Input obo: You are setting reverseWord first to boo, then to "oob" ("o" + "ob" + ""), discarding the first value.

I think you need to think your logic through once more.

Tip: learn to use a debugger.

You're condition isn't true because the way you build the reversed word is wrong.

1. You're beginning with i equals to 0
   


2. You reassign a new value to reverseWord in every loop


3. The way you're building the reversed string is totally a mystery to me

A good solution would be the following (you write the code :))

1. Try beginning your loops with the index beginning at the very end of the original word


2. Loop down until you reach 0, basically until no letter remains to be appended to reverseWord
   


3. In every loop, append a single letter to reverseWord instead of the result of a complex operation

• No need to make a new reference for the plaindrome word that you're going to check.


• You should store the word in the reverse order in reverseWord variable.


• Last index of a char array (String) in java is 1 less than string length. First index is 0.


• 
  

  So,the while loop read the string from the end to start index and store.

  
  
  

  public static boolean palindrome(String p)
  
   String reverseWord = "";
   int i = p.length() - 1;
   while (i >= 0)
   reverseWord += p.charAt(i);
   i--;
   
  
   if (reverseWord.equals(p)) 
   return true;
   
  
   return false;