#include <bits/stdc++.h>
using namespace std;
class Solution
{
private:
stack<int>stack1;
stack<int>stack2;
public:
void push(int node)
{
stack1.push(node);
}
int pop()
{
if(stack2.size()!=0)
{
int tmp = stack2.top();
stack2.pop();
return tmp;
}
else
{
while (stack1.size()!=0)
{
int tmp = stack1.top();
stack1.pop();
stack2.push(tmp);
}
return pop();
}
}
};
int main()
{
system(“pause”);
return 0;
}