2016暑假多校联合---To My Girlfriend

#include<bits/stdc++.h>  
using namespace std;  
#define LL long long  
const int maxn = 1005;  
const int mod = 1e9+7;  
int a[maxn];  
int dp[maxn][maxn][3][3];  
int n,s;  

int main()  
{  
    int T;  
    scanf("%d",&T);  
    while(T--)  
    {  
        memset(dp,0,sizeof(dp));  
        scanf("%d%d",&n,&s);  
        for(int i = 1;i<=n;i++)  
            scanf("%d",&a[i]);  
        dp[0][0][0][0]=1;  
        for(int i = 1;i<=n;i++)  
        for(int j = 0;j<=s;j++)  
        for(int s1 = 0;s1<=2;s1++)  
        for(int s2 = 0;s2<=2;s2++)  
        {  
            dp[i][j][s1][s2]=(dp[i][j][s1][s2]+dp[i-1][j][s1][s2])%mod;  
            if(j>=a[i])  
            dp[i][j][s1][s2]=(dp[i][j][s1][s2]+dp[i-1][j-a[i]][s1][s2])%mod;  
            if(s1>0&&j>=a[i])  
            dp[i][j][s1][s2]=(dp[i][j][s1][s2]+dp[i-1][j-a[i]][s1-1][s2])%mod;  
            if(s2>0)  
            dp[i][j][s1][s2]=(dp[i][j][s1][s2]+dp[i-1][j][s1][s2-1])%mod;  
        }  
        LL ans = 0;  
        for(int i = 1;i<=s;i++)  
          ans = (ans+dp[n][i][2][2])%mod;  
        printf("%lld\n",ans*4%mod);  
    }  
}