C++-stack：stack基本用法【stk.push(x)、stk.top()、stk.pop()、stk.size()、stk.empty()】

忘是亡心i 2023-09-25 13:48 24阅读 0赞

#### stack ####

> 栈是基本的[数据结构][Link 1]之一,特点是`先进后出`,就如开进死胡同的车队,先进去的只能最后出来.

在c++ 中,stack的[头文件][Link 2]是`#include<stack>`

#### stack常用操作 ####

stack<int> q;	//以int型为例
    int x;
    q.push(x);		//将x压入栈顶
    q.top();		//返回栈顶的元素
    q.pop();		//删除栈顶的元素
    q.size();		//返回栈中元素的个数
    q.empty();		//检查栈是否为空,若为空返回true,否则返回false

#include<iostream>
    #include<stack>
    using namespace std;
    int main()
    {
    	stack<int>  q;
    	q.push(1);
    	q.push(2);
    	q.push(3);
    	q.push(4);
    	q.push(5);
    	
    	cout<<"q.size "<<q.size()<<endl;
    	cout<<"q.top "<<q.top()<<endl;   //输出栈顶元素 
    	
    	q.pop();	//删除栈顶元素
    			
    	cout<<"q.size "<<q.size()<<endl;  
    	cout<<"q.top "<<q.top()<<endl;
    	
    	return 0; 
    }

![c8990ecc01cf42c19e534883c4fa2f4d.png][]

#### 例题 ####

题目: [51Nod - 3199 操作栈][51Nod - 3199]

代码

#include<iostream>
    #include<stack>
    using namespace std;
    int main()
    {
    	stack<int>  q;
    	int n,op,x;
    	
    	cin>>n;
    	while(n--)
    	{
    		cin>>op;
    		if(op==1)
    		{
    			cin>>x;
    			q.push(x);
    		}
    		else if(op==2)
    		{
    			if(q.empty())
    				cout<<"empty"<<endl;
    			else
    			{
    				cout<<q.top()<<endl;
    				q.pop();
    			}
    		}
    	}
    	return 0; 
    }

--------------------

[c++ set用法详解][c_ set]

[Link 1]: https://so.csdn.net/so/search?q=%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84&spm=1001.2101.3001.7020
[Link 2]: https://so.csdn.net/so/search?q=%E5%A4%B4%E6%96%87%E4%BB%B6&spm=1001.2101.3001.7020
[c8990ecc01cf42c19e534883c4fa2f4d.png]: https://img-blog.csdnimg.cn/c8990ecc01cf42c19e534883c4fa2f4d.png
[51Nod - 3199]: https://vjudge.net/problem/51Nod-3199
[c_ set]: https://blog.csdn.net/weixin_52341477/article/details/119248919