HDU 1702 http://acm.hdu.edu.cn/showproblem.php?pid=1702

#include<stdio.h>
#include<string.h>
#include<queue>
#include<stack>
#define N 10
using namespace std;

void Q(int n)
{
    int m;
    char s[N];
    queue<int>Q;
    while(n--)
    {
        scanf("%s", s);
        if(strcmp(s, "IN") == 0)
        {
            scanf("%d", &m);
            Q.push(m);
        }
        else if(strcmp(s, "OUT") == 0)
        {
            if(Q.empty())
                printf("None\n");
            else
            {
                printf("%d\n", Q.front());
                Q.pop();
            }
        }
    }
}

void S(int n)
{
    stack<int>S;
    char s[N];
    int m;
    while(n--)
    {
        scanf("%s", s);
        if(strcmp(s, "IN") == 0)
        {
            scanf("%d", &m);
            S.push(m);
        }
        else if(strcmp(s, "OUT") == 0)
        {
            if(S.empty())
            {
                printf("None\n");
            }
            else
            {
                printf("%d\n", S.top());
                S.pop();
            }
        }
    }
}
int main()
{
    int t, n;
    char s[N];
    scanf("%d", &t);
    while(t--)
    {
        scanf("%d%s", &n, s);
        if(strcmp(s, "FIFO") == 0)
            Q(n);
        else if(strcmp(s, "FILO") == 0)
            S(n);
    }
    return 0;
}