#include <bits/stdc++.h>   using namespace std;   const int big = ((long long int)1 << 30);   const long long int mod = 1000000007;   int main(void) {     int n, m, ans = 0, i, q, w, gen = 0;     vector<int> kaz;     vector<bool> uma;     scanf( %d %d , &n, &m);     m--;     kaz.resize(n);     uma.resize(n + 1);     for (i = 0; i < n; i++) {       scanf( %d , &q);       if (i == m && q != 0) {         ans++;         q = 0;       }       if (i != m && q == 0) {         q = n;       }       kaz[i] = q;       uma[q] = 1;     }     sort(kaz.begin(), kaz.end());     while (-1) {       for (; gen <= n; gen++) {         if (uma[gen] == 0) {           break;         }       }       if (kaz.back() <= gen) {         break;       }       ans++;       kaz.pop_back();       uma[gen] = 1;     }     printf( %d n , ans);     return 0;   }   