#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x;
  while (scanf("%d %d", &n, &x) == 2) {
    vector<int> arr(n, 0);
    for (int i = 0; i < n; i++) {
      scanf("%d", &arr[i]);
    }
    sort(arr.begin(), arr.end());
    int banyak = 0;
    for (int i = 0; i < x; i++) {
      vector<int>::iterator it = lower_bound(arr.begin(), arr.end(), i);
      if (*it != i) banyak++;
    }
    vector<int>::iterator it = lower_bound(arr.begin(), arr.end(), x);
    if (*it == x) banyak++;
    cout << banyak << endl;
  }
  return 0;
}
