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class MyStack {
    queue<int> Q;

public:
    MyStack() {}

    void push(int x) {
        queue<int> temp;
        temp.push(x);
        while (!Q.empty()) {
            temp.push(Q.front());
            Q.pop();
        }
        Q = temp;
    }

    int pop() {
        int x = Q.front();

        Q.pop();

        return x;
    }

    int top() { return Q.front(); }

    bool empty() { return Q.empty(); }
};

/**
 * Your MyStack object will be instantiated and called as such:
 * MyStack* obj = new MyStack();
 * obj->push(x);
 * int param_2 = obj->pop();
 * int param_3 = obj->top();
 * bool param_4 = obj->empty();
 */