java.

comment both codes out for everyline. explain the code. will give thumps up

import java.util.Scanner;

public class Main {

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

System.out.println("Palindrome Checker.");

System.out.println("Note: This palindrome checker is not case-sensitive and will ignore spaces.");

for (;;) {

System.out.print("Enter word (or 'quit' to exit): ");

String input = scanner.nextLine();

if (input.equals("quit")) {

break;

}

Deque deque = new Deque<>();

for (int i = 0; i < input.length(); i++) {

char ch = input.charAt(i);

if (Character.isLetterOrDigit(ch)) {

deque.addBack(Character.toLowerCase(ch));

}

}

boolean isPalindrome = true;

for (; deque.length() > 1; ) {

char front = deque.removeFront();

char rear = deque.removeBack();

if (front != rear) {

isPalindrome = false;

break;

}

}

if (isPalindrome) {

System.out.println("Yes - That is a palindrome ");

} else {

System.out.println("No - That is not a palindrome ");

}

}

scanner.close();

}

}

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