#include <bits/stdc++.h>
int main() {
  int n, x;
  std::cin >> n >> x;
  std::vector<int> data;
  int counter = 0;
  for (int i = 0; i != n; i++) {
    int temp;
    std::cin >> temp;
    data.push_back(temp);
  }
  std::sort(data.begin(), data.end());
  if (std::find(data.begin(), data.end(), x) != data.end()) {
    auto it = std::find(data.begin(), data.end(), x);
    counter++;
    data.erase(it);
  }
  for (int i = 0; i < x; i++) {
    if (std::find(data.begin(), data.end(), i) == data.end()) {
      data.push_back(i);
      counter++;
    }
  }
  std::cout << counter << std::endl;
  return 0;
}
