Data-Structures-and-Algorithms/232_queue_2_stacks.py at main · rasimatics/Data-Structures-and-Algorithms · GitHub

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class MyQueue:

    def __init__(self):
        self.pop_stack = []
        self.push_stack = []


    def push(self, x: int) -> None:
        self.push_stack.append(x)


    def pop(self) -> int:
        if self.pop_stack:
            return self.pop_stack.pop()

        while self.push_stack:
            self.pop_stack.append(self.push_stack.pop())

        return self.pop_stack.pop()


    def peek(self) -> int:
        if self.pop_stack:
            return self.pop_stack[-1]
        return self.push_stack[0]


    def empty(self) -> bool:
        return not(self.push_stack or self.pop_stack)


# Your MyQueue object will be instantiated and called as such:
# obj = MyQueue()
# obj.push(x)
# param_2 = obj.pop()
# param_3 = obj.peek()
# param_4 = obj.empty()