HDOJ 1702 ACboy needs your help again! (stack & queue)

ACboy needs your help again!

Time Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)

Total Submission(s): 4616 Accepted Submission(s): 2370

[align=left]Problem Description[/align]
ACboy was kidnapped!!

he miss his mother very much and is very scare now.You can't image how dark the room he was put into is, so poor :(.

As a smart ACMer, you want to get ACboy out of the monster's labyrinth.But when you arrive at the gate of the maze, the monste say :" I have heard that you are very clever, but if can't solve my problems, you will die with ACboy."

The problems of the monster is shown on the wall:

Each problem's first line is a integer N(the number of commands), and a word "FIFO" or "FILO".(you are very happy because you know "FIFO" stands for "First In First Out", and "FILO" means "First In Last Out").

and the following N lines, each line is "IN M" or "OUT", (M represent a integer).

and the answer of a problem is a passowrd of a door, so if you want to rescue ACboy, answer the problem carefully!

[align=left]Input[/align]
The input contains multiple test cases.

The first line has one integer,represent the number oftest cases.

And the input of each subproblem are described above.

[align=left]Output[/align]
For each command "OUT", you should output a integer depend on the word is "FIFO" or "FILO", or a word "None" if you don't have any integer.

[align=left]Sample Input[/align]

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

[align=left]Sample Output[/align]

1
2
2
1
1
2
None
2
3

题目链接：HDOJ 1702 ACboy needs your help again! (stack & queue)

FILO 先进后出 用 栈 （stack）

FIFO 先进先出 用队列 （queue）

IN OUT 分别是 进 出 队列 或 栈

已AC代码：

#include<cstdio>
#include<cstring>
#include<stack>
#include<queue>
using namespace std;

queue<int>Q;
stack<int>S;

int main()
{
int T,n,a;
char str[50],ch[50];
scanf("%d",&T);
while(T--)
{
scanf("%d%s",&n,str);

while(!S.empty())//清空栈
S.pop();
while(!Q.empty())//清空队列
Q.pop();

if(strcmp(str,"FILO")==0) //栈先进后出
{
while(n--)
{
scanf("%s",ch);
if(strcmp(ch,"IN")==0)
{
scanf("%d",&a);
S.push(a);
}
else if(strcmp(ch,"OUT")==0)
{
if(S.empty())
printf("None\n");
else
{
printf("%d\n",S.top());
S.pop();
}
}
}
}
else if(strcmp(str,"FIFO")==0) //队列先进先出
{
while(n--)
{
scanf("%s",ch);
if(strcmp(ch,"IN")==0)
{
scanf("%d",&a);
Q.push(a);
}
else if(strcmp(ch,"OUT")==0)
{
if(Q.empty())
printf("None\n");
else
{
printf("%d\n",Q.front());
Q.pop();
}
}
}
}
}
return 0;
}