UVA 1594 set 里面放queue

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<string>
#include<queue>
#include<set>
#include<vector>
#define maxn 20
using namespace std;
typedef queue<int> Q;
int main(){
    set<Q> se;
    int t,n,a[maxn],flag=1,ff[maxn],nn=0;
    scanf("%d",&t);
    while(t--){
    nn=0;
    flag=1;
    scanf("%d",&n);
    Q q;
    se.clear();
    memset(a,0,sizeof(a));
    memset(ff,0,sizeof(ff));
    for(int i=0;i<n;i++){
        scanf("%d",&a[i]);
        if(a[i]==0) nn++;
        q.push(a[i]);
    }
    if(nn==n){
        printf("%s\n","ZERO");
        flag=0;
    }
    se.insert(q);

    while(flag==1){
    int f=q.front(),m,b;
    int x=f;
    q.pop();
    int j=0;
    for(int i=1;i<n;i++){
        m=q.front();
        q.pop();
        b=abs(f-m);
        q.push(b);
        ff[j++]=b;
        f=m;
    }
    q.push(abs(x-f));
    ff[j++]=abs(x-f);
    if(!se.count(q)){se.insert(q);}
    else{
        printf("%s\n","LOOP");
        flag=0;
    }

     nn=0;
    for(int k=0;k<j;k++){
        if(ff[k]==0) nn++;
    }
    if(nn==n) {
        printf("%s\n","ZERO");
        flag=0;
    }


    }
   }
  return 0;
}