NTHU OJ

NTHU OJ - 5710 Stack (Use C++ Standard Library).cpp

//This program is for NTHU 5710 Stack
//題目來源 Problem link: http://140.114.86.38/problem.php?pid=5710
 
#include<iostream>
#include<stdio.h>
#include<stack>
#include<string.h>
using namespace std;
 
stack<int> s;
 
void stackClear()
{
    while( !s.empty())
        s.pop();
}
 
void stackTop()
{
    if(s.size() == 0)
        printf("X\n");
    else
        printf("%d\n", s.top());
}
 
void stackPush(int n)
{
    s.push(n);
}
 
void stackPop()
{
    if( !s.empty())
        s.pop();
}
 
void stackAction(char action[])
{
    if(strcmp(action, "top") == 0)
        stackTop();
    else if(strcmp(action, "push") == 0)
    {
        int tmp;
        scanf("%d", &tmp);
        stackPush(tmp);
    }
    else if(strcmp(action, "pop") == 0)
        stackPop();
}
 
int main()
{
    char oper[5];
 
    stackClear();
 
    while(scanf("%s", &oper) != EOF)
    {
        stackAction(oper);
    }
    return 0;
}