#pragma GCC optimize("Ofast", "unroll-loops")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

#define ll long long

constexpr ll mod = 1000000007LL;

int N, K;
vector<int> A;

void input(void){
    cin >> N >> K;
    A.resize(N);
    for (int& ai : A)
        cin >> ai;
}

constexpr int offset = 10000;

ll solve(void){
    for (int& ai : A)
        ai -= K;
    vector<vector<ll>> dp(
        N + 1, vector<ll>(2 * offset + 1, 0)
    );
    dp[0][offset] = 1;
    for (int i = 1; i <= N; ++i){
        int a = A[i - 1];
        for (int s = 0; s <= 2 * offset; ++s){
            dp[i][s] = dp[i - 1][s];
            if (0 <= s - a && s - a <= 2 * offset)
                dp[i][s] = (dp[i][s] + dp[i - 1][s - a]) % mod;
        }
    }
    ll ret = 0;
    for (int s = offset; s <= 2 * offset; ++s)
        ret = (ret + dp[N][s]) % mod;
    return (ret + mod - 1) % mod;
}

int main(void){
    input();
    cout << solve() << endl;
    return 0;
}