HDU - 1702 ACboy needs your help again!（栈和队列）

Sample Input
4
4 FIFO
IN 1
IN 2
OUT
OUT
4 FILO
IN 1
IN 2
OUT
OUT
5 FIFO
IN 1
IN 2
OUT
OUT
OUT
5 FILO
IN 1
IN 2
OUT
IN 3
OUT
Sample Output
1
2
2
1
1
2
None
2
3

 1 #include<stdio.h>
 2 #include<string.h>
 3 #include<math.h>
 4 #include<queue>
 5 #include<algorithm>
 6 #include<time.h>
 7 #include<stack>
 8 using namespace std;
 9 #define N 1000
10 #define INF 0x3f3f3f3f
11 
12 int main()
13 {
14     int T,i,a,n;
15     char s[N],str[N];
16 
17     scanf("%d", &T);
18 
19     while(T--)
20     {
21         scanf("%d %s", &n , s);
22 
23         if(s[2]==‘F‘)///存入队列
24         {
25             queue<int >Q;
26             for(i=0;i<n;i++)
27             {
28                 scanf("%s", str);
29                 if(str[0]==‘I‘)
30                 {
31                     scanf("%d", &a);
32                     Q.push(a);
33                 }
34                 else
35                 {
36                     if(Q.empty())
37                         printf("None\n");
38                     else
39                     {
40                         int x=Q.front();
41                         Q.pop();
42                         printf("%d\n", x);
43                     }
44                 }
45             }
46         }
47         else
48         {
49             stack<int >P;
50             for(i=0;i<n;i++)
51             {
52                 scanf("%s", str);
53 
54                 if(str[0]==‘I‘)
55                 {
56                     scanf("%d",&a);
57                     P.push(a);
58                 }
59                 else
60                 {
61                     if(P.empty())
62                         printf("None\n");
63                     else
64                     {
65                         int x=P.top();
66                         P.pop();
67                         printf("%d\n", x);
68                     }
69                 }
70             }
71         }
72     }
73 
74     return 0;
75 }