#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x, ptr, i, count = 0;
  cin >> n >> x;
  int a[n];
  for (i = 0; i < n; ++i) {
    cin >> a[i];
  }
  sort(a, a + n);
  for (i = 0; i < n; ++i) {
    if (a[i] == x) {
      count++;
      ptr = i;
      break;
    } else if (a[i] > x) {
      ptr = i;
      break;
    }
  }
  ptr = i;
  count += x - ptr;
  cout << count << endl;
}
