#include <bits/stdc++.h>
using namespace std;
int main() {
  int a[105];
  int n, m;
  scanf("%d %d", &n, &m);
  for (int i = 0; i < n; i++) scanf("%d", a + i);
  sort(a, a + n);
  int ji1 = 0, ji2 = 0;
  for (int i = 0; i < n; i++) {
    if (a[i] < m)
      ji1++;
    else if (a[i] == m)
      ji2++;
    else
      break;
  }
  ji2 += (m - ji1);
  printf("%d\n", ji2);
}
