class Stack:
    def __init__(self):
        self.stack = []

    def push(self, item):
        self.stack.append(item)

    def pop(self):
        if not self.is_empty():
            return self.stack.pop()

    def peek(self):
        if not self.is_empty():
            return self.stack[-1]

    def is_empty(self):
        return len(self.stack) == 0

    def size(self):
        return len(self.stack)
	
	# Zadanie dodatkowe
    def is_equal(self, other):
        if self.size() != other.size():
            return False
        for i in range(self.size()):
            if self.stack[i] != other.stack[i]:
                return False
        return True

stack = Stack()

stack.push(1)
stack.push(2)
stack.push(3)

print(stack.pop())  # 3
print(stack.peek())  # 2
print(stack.is_empty())  # False
print(stack.size())  # 2




class Queue:
    def __init__(self):
        self.queue = []

    def is_empty(self):
        return len(self.queue) == 0

    def enqueue(self, item):
        self.queue.append(item)

    def dequeue(self):
        if not self.is_empty():
            return self.queue.pop(0)

    def peek(self):
        if not self.is_empty():
            return self.queue[0]

queue = Queue()

queue.enqueue(1)
queue.enqueue(2)
queue.enqueue(3)

print(queue.dequeue())  # 1
print(queue.dequeue())  # 2
print(queue.is_empty())  # False
print(queue.dequeue())  # 3
print(queue.is_empty())  # True


def reverse_list(input_list):
    stack = Stack()
    reversed_list = []
    
    for item in input_list:
        stack.push(item)
    
    while not stack.is_empty():
        reversed_list.append(stack.pop())
        
    return reversed_list

def remove_duplicates(q):
    new_q = Queue()
    while not q.is_empty():
        item = q.dequeue()
        if item not in new_q.queue:
            new_q.enqueue(item)
    return new_q


def is_palindrome(string):
    stack = Stack()
    for char in string:
        stack.push(char)
    reversed_string = ""
    while not stack.is_empty():
        reversed_string += stack.pop()
    return string == reversed_string