HDU1702 ACboy needs your help again!

#include<iostream>
#include<string>
#include<queue>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdio>
#include<map>
#include<vector>
#include<queue>
#include<stack>
#define maxn 10010
using namespace std;
int main()
{
char s1[10],s2[10];
int t,n,i,m;
while (scanf("%d",&t)!=EOF && t)
{

while(t--)
{
scanf("%d%s",&n,s1);
if(s1[2]=='F')
{
queue<int> q;
for(i=0;i<n;i++)
{
scanf("%s",s2);
if(s2[0]=='I')
{
scanf("%d",&m);
q.push(m);
}
else
{
if(q.empty())
printf("None\n");
else
{
printf("%d\n",q.front());
q.pop();
}
}
}
}
else
{
stack<int> p;
for(i=0;i<n;i++)
{
scanf("%s",s2);
if(s2[0]=='I')
{
scanf("%d",&m);
p.push(m);
}
else
{
if(p.empty())
printf("None\n");
else
{
printf("%d\n",p.top());
p.pop();
}
}
}
}
}
}
return 0;
}