#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007;
int main(){
  int N, K;
  cin >> N >> K;
  vector<int> A(N);
  for (int i = 0; i < N; i++){
    cin >> A[i];
  }
  vector<vector<long long>> dp(N + 1, vector<long long>(20001, 0));
  dp[0][10000] = 1;
  for (int i = 0; i < N; i++){
    dp[i + 1] = dp[i];
    for (int j = 0; j <= 20000; j++){
      int j2 = j + A[i] - K;
      if (0 <= j2 && j2 <= 20000){
        dp[i + 1][j2] += dp[i][j];
        dp[i + 1][j2] %= MOD;
      }
    }
  }
  long long ans = 0;
  for (int i = 10000; i <= 20000; i++){
    ans += dp[N][i];
  }
  ans += MOD - 1;
  ans %= MOD;
  cout << ans << endl;
}