1.先说说stack吧
栈只支持栈顶操作，典型的先入先出，LAST I N FIRST OUT
stack<int>s;
基本操作是
s.push(压入的元素)
s.size()栈元素个数
s.pop();弹出栈顶元素
s.top()返回栈顶元素
s.empty()栈为空时则返回真
#include<cstdio>
#include<stack>
using namespace std;
int main()
{
stack<int>s;
s.push(1);
printf("zhandingshi %d\n",s.top());
printf("zhanzhongyuansugeshushi %d\n",s.size());
s.push(12);
printf("zhandingshi %d\n",s.top());
printf("zhanzhongyuansugeshushi %d\n",s.size());
s.push(13);
printf("zhandingshi %d\n",s.top());
printf("zhanzhongyuansugeshushi %d\n",s.size());
s.pop();
printf("zhandingshi %d\n",s.top());
printf("zhanzhongyuansugeshushi %d\n",s.size());
s.pop();
printf("zhandingshi %d\n",s.top());
printf("zhanzhongyuansugeshushi %d\n",s.size());
s.pop();
// printf("zhandingshi %d\n",s.top());
//printf("zhanzhongyuansugeshushi %d\n",s.size());
return 0;
}