改了一上午结果top写成pop.....

#include<bits/stdc++.h>
using namespace std;

stack<int> q;

void spush(int x){
    q.push(x);
}

void spop(){
    if(q.empty()) cout << "pop fail" << endl;
    else{
        cout << "pop " << q.top() << endl;
        q.pop();
    }
}

void stop(){
    if(q.empty()) cout << "top fail" << endl;
    else cout << "top = " << q.top() << endl;
}

void ssize(){
    cout << "size = " << q.size() << endl;
}

void sempty(){
    if(q.empty()) cout << "yes" << endl;
    else cout << "no" << endl;
}

int main(){
    int n;
    cin >> n;
    while(n--){
        string s;
        int x;
        cin >> s;
        if(s=="push"){
            cin >> x;
            spush(x);
        }else if(s=="pop"){
            spop();
        }else if(s=="top"){
            stop();
        }else if(s=="empty"){
            sempty();
        }else if(s=="size"){
            ssize();
        }
    }
}