class MinStack {
public:
    /** initialize your data structure here. */
    int a[10001];
    int b[10001];
    int at=-1;
    int bt=-1;
    MinStack() {

    }

    void push(int x) {
        a[++at]=x;
        if(bt!=-1)
        {
            if(x<=b[bt])
            {
                b[++bt]=x;
            }
        }
        else
        {
            b[++bt]=x;
        }
    }

    void pop() {
        at--;
        if(a[at+1]==b[bt])
        {
            bt--;
        }
    }

    int top() {

        return a[at];
    }

    int getMin() {
        return b[bt];
    }
};

/**
 * Your MinStack object will be instantiated and called as such:
 * MinStack obj = new MinStack();
 * obj.push(x);
 * obj.pop();
 * int param_3 = obj.top();
 * int param_4 = obj.getMin();
 */