#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<climits>
#include<cstdlib>
#include<ctime>
#include<cctype>
#include<algorithm>
#include<set>
#include<map>
#include<vector>
#include<stack>
#include<queue>
#include<deque>
#include<string>
#include<sstream>
#include<iomanip>
using namespace std;
//=====================struct declaration======================

//=====================var declarartion========================
const int maxn=100+10;
int a[maxn],f[maxn][maxn];

int n,m;
//=====================function declaration====================

//=====================main code===============================
int main()
{
	freopen("flower.in","r",stdin);
	freopen("flower.out","w",stdout);
	
	
	scanf("%d%d",&n,&m);
	
	for(int i=1; i<=n; i++)
		scanf("%d",&a[i]);
		
	for(int i=0; i<=a[1]; i++)
		f[1][i]=1;
	
	for(int i=2; i<=n; i++)
	for(int j=0; j<=m; j++)
	{
		int t=0;
		for(int k=0; k<=a[i]; k++)
		{
			if(j-k>=0)
				t+=f[i-1][j-k];
			f[i][j]=t%1000007;
		}
	}
	
	printf("%d\n",f[n][m]);
	
	return 0;
}
//=====================function code===========================