There is a PHP error with the code provided.

PHP Fatal error: Array and string offset access syntax with curly braces is no longer supported in Solution.php on line 34

code in java 15 class solution {

ArrayDeque ad1=new ArrayDeque(); //for stack ArrayDeque ad2=new ArrayDeque(); //for queue

void pushCharacter(char ch)
{
    ad1.push(ch);

}
void enqueueCharacter(char ch)
{
    ad2.add(ch);
}


char popCharacter()
{
    return (char)ad1.pop();
}

char dequeCharacter()
{
    return (char)ad2.poll();
}





public static void main(String[] args) {

    Scanner sc=new Scanner(System.in);
    String s=sc.nextLine();
    Solution p=new Solution();
    for(int i=0;i<s.length();i++)
    {
        p.pushCharacter(s.charAt(i));
        p.enqueueCharacter(s.charAt(i));
    }

    boolean b=true;
    for(int i=0;i<s.length()/2;i++)
    {
        if(p.popCharacter()!=p.dequeCharacter())
        {
            b=false;
            break;
        }
    }
    if(b)
    {
        System.out.println("The word, "+s+", is a palindrome.");
    }
    el
            }se
    {
    System.out.println("The word, "+s+", is not a palindrome.");
    }
}

def init(self): self.stack = [] self.queue = []

def pushCharacter(self, char):
    self.stack.append(char)

def enqueueCharacter(self, char):
    self.queue.append(char)

def popCharacter(self):
    if len(self.stack) == 0:
        return None
    return self.top()
    self.stack = self.stack[:-1]

def top(self):
    if len(self.stack) == 0:
        return None
    return self.stack[-1]

def dequeueCharacter(self):
    if len(self.queue) == 0:
        return None
    return self.front()
    self.queue = self.queue[1:]

def front(self):
    if len(self.queue) == 0:
        return None
    return self.queue[0]

Java

public class Solution {
    // Write your code here.
     Stack<Character> stack = new Stack<>();
    Queue<Character> queue = new LinkedList<>();
    public void pushCharacter(char c)
    {
        stack.push(c);
    }
    public void enqueueCharacter(char c)
    {
        queue.add(c);
    }
    public char popCharacter()
    {
        return stack.pop();
    }
    public char dequeueCharacter()
    {
        return queue.remove();
    }

IMO these challanges are getting easier every week. *Pyhon code: *

def __init__(self):
        self.queue = []
        self.stack = []

    def pushCharacter(self, char):
        self.stack.append(char)
    def enqueueCharacter(self, char):
        self.queue.append(char)
    def popCharacter(self):
        return self.stack.pop(-1)
    def dequeueCharacter(self):
        return self.queue.pop(0)