#include <bits/stdc++.h>
using namespace std;

int main() {
    constexpr int64_t mod = 1000000007;
    int n, k;
    cin >> n >> k;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        a[i] -= k;
    }
    vector<vector<int64_t>> dp(n + 1, vector<int64_t>(20001));
    dp[0][10000] = 1;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j <= 20000; j++) {
            dp[i + 1][j] += dp[i][j];
            dp[i + 1][j] %= mod;
            int j_next = j + a[i];
            if (0 <= j_next and j_next <= 20000) {
                dp[i + 1][j_next] += dp[i][j];
                dp[i + 1][j_next] %= mod;
            }
        }
    }
    int64_t ans = mod - 1;
    for (int i = 10000; i <= 20000; i++) {
        ans += dp[n][i];
        ans %= mod;
    }
    cout << ans << endl;
}