class Solution
{
public:
    void push(int node) {
        stack1.push(node);
    }

    int pop() {
        if(stack2.empty()){
            while(!stack1.empty()){//保证栈2为空
            stack2.push(stack1.top());//本质就是把栈1中的值放到栈2中,实现反转
                        stack1.pop();
        }
        }
        
        int temp=stack2.top();
        stack2.pop();
        return temp;
    }

private:
    stack<int> stack1;
    stack<int> stack2;
};