N, K = map(int, input().split())
A = list(map(lambda x:int(x)-K, input().split()))
dp = [0]*20001
dp[0] = 1
mod = 10**9+7
for i in range(N):
  new_dp = dp[:]
  for j in range(-10000,10001):
    if -10000<=j+A[i]<=10000:
      new_dp[j+A[i]] += dp[j]
      new_dp[j+A[i]] %= mod
  dp = new_dp
ans = -1
for i in range(10001):
  ans += dp[i]
print(ans%mod)