#include <fstream>
using namespace std;
int f[101][101];
int mark(int x,int y)
{
	if(x<y)return x;
	else return y;
}
int main()
{
	int n,m,a[101],i,j,k,sum=0,l;
	ifstream in("flower.in");
	ofstream out("flower.out");
	in>>n>>m;
	for(i=1;i<=n;i++)in>>a[i];
	for(i=1;i<=n;i++)
	{
		for(j=1;j<=m;j++)
		{
			f[i][j]=0;
		}
	}
	for(i=1;i<=n;i++)
	{
		for(j=1;j<=m;j++)
		{
			if(i==1||j<=a[1])f[i][j]=1;
			if(i>=2||j>=0)
			{
				l=mark(j,a[i]);
				for(k=0;k<=l;k++)
				{
					f[i][j]=f[i][j]+f[i-1][j-k];
				}
			}
			sum=0;
			f[i][j]=f[i][j]%1000007;
		}
	}
	out<<f[n][m];
	in.close();
	out.close();
	return 0;
}