LeetCode-Daily-Challenge/Implement Queue using Stacks.cpp at main · blindaks/LeetCode-Daily-Challenge · GitHub

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class MyQueue {
public:
stack<int>st;
    MyQueue() {

    }

    void push(int x) {
        st.push(x);
    }

    int pop() {
        stack<int>s;
        while(st.size()!=1)
        {
            s.push(st.top());
            st.pop();
        }
        int x=st.top();
        st.pop();
        while(!s.empty())
        {
            st.push(s.top());
            s.pop();
        }
        return x;
    }

    int peek() {
        stack<int>s;
        while(st.size()!=1)
        {
            s.push(st.top());
            st.pop();
        }
        int x=st.top();
        while(!s.empty())
        {
            st.push(s.top());
            s.pop();
        }
        return x;
    }

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

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