#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x;
  scanf("%d%d", &n, &x);
  int arr[n];
  for (int i = 0; i < n; i++) {
    scanf("%d", &arr[i]);
  }
  sort(arr, arr + n);
  int i = 0;
  while (arr[i] < x) i++;
  int op = x - i;
  if (arr[i] == x) op++;
  cout << op << endl;
}
