#include <bits/stdc++.h>
using namespace std;
int main() {
  int arr[101] = {0};
  int operation = 0, current = 0;
  int n, x;
  cin >> n >> x;
  for (int i = 0; i < n; i++) {
    cin >> current;
    arr[current]++;
    current = 0;
  }
  if (x == 0) {
    if (arr[0] == 0)
      operation = 0;
    else
      operation = 1;
  } else {
    for (int i = 0; i < x; i++) {
      if (arr[i] == 0) operation++;
    }
    if (arr[x] != 0) operation++;
  }
  cout << operation;
}
