#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x, sc = 0, y;
  cin >> n >> x;
  int A[101];
  for (int i = 0; i < 101; i++) {
    A[i] = 0;
  }
  for (int i = 0; i < n; i++) {
    cin >> y;
    A[y] = 1;
  }
  if (A[x] == 1) sc++;
  for (int i = x - 1; i >= 0; i--) {
    if (A[i] == 0) sc++;
  }
  cout << sc;
}
