#include <bits/stdc++.h>
using namespace std;
long long dp[51][51][2501];
int main() {
  int N, A;
  cin >> N >> A;
  vector<int> a(N);
  for (auto &x : a) cin >> x;
  dp[0][0][0] = 1;
  for (int i = 0; i < N; i++) {
    for (int picked = 0; picked <= 50; picked++) {
      for (int sum = 0; sum <= i * 50; sum++) {
        dp[i + 1][picked + 1][sum + a[i]] += dp[i][picked][sum];
        dp[i + 1][picked][sum] += dp[i][picked][sum];
      }
    }
  }
  long long ans = 0;
  for (int picked = 1; picked <= N; picked++) ans += dp[N][picked][picked * A];
  cout << ans;
  return 0;
}
