HDU 5776 sum

http://blog.youkuaiyun.com/queuelovestack/article/details/52075208#comments
别人写的太好了，借鉴借鉴

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<queue>
#include<stack>
#include<math.h>
#include<vector>
#include<algorithm>
#include<iostream>

using namespace std;

const int N = 100005;
const int M = 5005;
const int inf = 1000000007;
const int mod = 1000000007;

int a[N];///前缀和（预处理后的）
int v[N];

int main()
{
    int T,m,n,x,key;
    cin>>T;
    while(T--){
        memset(a,0,sizeof(a));
        memset(v,0,sizeof(v));///
        cin>>n>>m;
        a[0]=0;
        for(int i=1;i<=n;i++){
            cin>>x;
            a[i]=(a[i-1]+x)%m;
        }

        key=0;
        for(int i=0;i<=n;i++)//从0开始是因为前缀和取模为0出现一次就可认定区间元素之和是m的倍数
        {
            if( v[a[i]]==1 )
            {
                cout<<"YES"<<endl;
                key=1;
                break;
            }
            v[a[i]]=1;
        }
        if(key==0)cout<<"NO"<<endl;
    }
    return 0;
}