n, k = map(int, input().split())
a = list(map(int, input().split()))
MOD = 10 ** 9 + 7


sum_a = sum(a)
dp = [[0] * (sum_a + 1) for i in range(n + 1)]
dp[0][0] = 1


for val in a:
    for i in range(n)[::-1]:
        for j in range(sum_a + 1)[::-1]:
            if j - val < 0:
                break
            dp[i + 1][j] += dp[i][j - val]
            dp[i + 1][j] %= MOD

ans = 0
for i in range(1, n + 1):
    ans += sum(dp[i][k * i:])
    ans %= MOD
print(ans)