import sys
import pypyjit
import itertools
import heapq
import math
from collections import deque, defaultdict
import bisect

input = sys.stdin.readline
sys.setrecursionlimit(10 ** 6)
pypyjit.set_param('max_unroll_recursion=-1')


def index_lt(a, x):
    'return largest index s.t. A[i] < x or -1 if it does not exist'
    return bisect.bisect_left(a, x) - 1


def index_le(a, x):
    'return largest index s.t. A[i] <= x or -1 if it does not exist'
    return bisect.bisect_right(a, x) - 1


def index_gt(a, x):
    'return smallest index s.t. A[i] > x or len(a) if it does not exist'
    return bisect.bisect_right(a, x)


def index_ge(a, x):
    'return smallest index s.t. A[i] >= x or len(a) if it does not exist'
    return bisect.bisect_left(a, x)


N, K = map(int, input().split())
A = list(map(int, input().split()))
mod = 10 ** 9 + 7

D = [a - K for a in A]
L = 20000
dp = [[0 for _ in range(L + 10)] for _ in range(N + 1)]
dp[0][10000] = 1
for i in range(N):
    for j in range(L + 1):
        if 0 <= j + D[i] <= L:
            dp[i + 1][j + D[i]] += dp[i][j]
            dp[i + 1][j + D[i]] %= mod
        dp[i + 1][j] += dp[i][j]
        dp[i + 1][j] %= mod
ans = 0
for j in range(10000, 20000 + 1):
    ans += dp[N][j]
    ans %= mod
print((ans - 1) % mod)