栈

include

include

using namespace std;
int main(){
stack s;
s.push(10);
s.push(20);
s.push(30);
cout<<"此时栈顶元素是"<<s.top()<<endl;
s.pop();
cout<<"此时栈顶元素是"<<s.top()<<endl;
s.pop();
s.pop();
if(s.empty()){
cout<<"空栈"<<endl;
}else{
cout<<"非空栈"<<endl;
}
return 0;
}