#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x;
  cin >> n >> x;
  map<long long, int> mapi;
  for (int i = 0; i < n; i++) {
    int a;
    cin >> a;
    mapi[a] = 1;
  }
  long long result = 0;
  for (int i = 0; i < x; i++) {
    if (!mapi[i]) result++;
  }
  if (mapi[x]) result++;
  cout << result << endl;
}
