每天几道面（笔）试题

1.两个栈实现一个队列、两个队列实现一个栈

//两个队列实现一个队列class Solution{public:    void push(int node)     {        stack1.push(node);    }    int pop()     {        if( stack2.size() <= 0)        {            while( stack1.size() > 0)            {                int data = stack1.top();                stack1.pop();                stack2.push(data);            }        }        int val = stack2.top();        stack2.pop();        return val;    }private:    stack<int> stack1;    stack<int> stack2;};//两个队列实现一个栈class Stack{public:    void push(int data)    {        queue1.push(data);    }    void pop()    {        while( !queue1.empty())        {            if( queue2.empty() )            {                while( queue1.size() != 1)                {                    int data = queue1.front();                    queue1.pop();                    queue2.push(data);                }                int data = queue1.front();                queue1.pop();                cout<<data<<" ";            }        }    }private:    queue<int> queue1;    queue<int> queue2;};