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#include<cstdio>
#define N 200010
#define NN 100000
#define MO 1000000007
int m,n,t,a[N],ans,st1[N],st2[N],top;
int main(){
    scanf("%d%d",&n,&m);
    st1[++top]=NN;
    st2[top]=1;
    for (int i=1;i<=n;i++){
        scanf("%d",&t);
        for (int j=0;j<=200000;j++)if (a[j]){
            st1[++top]=j;
            st2[top]=a[j];
            a[j]=0;
        }
        while (top){
            a[st1[top]+t]+=st2[top];
            a[st1[top]+t]%=MO;
            a[st1[top]-t]+=st2[top];
            a[st1[top]-t]%=MO;
            top--;
        }
    }
    printf("%d\n",a[m+NN]);
    return 0;
}
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