#include <bits/stdc++.h>
using namespace std;

//--------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define RFOR(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define LL long long
#define INF INT_MAX/3

//--------------------------------------------
const double EPS = 1e-14;
const double PI  = acos(-1.0);

//--------------------------------------------


int main(){
  vector <int> v;
  int n,m;
  int c;

  scanf("%d %d",&n,&m);
  REP(i,n) {
    scanf("%d",&c);
    v.push_back(c);
  }

  sort(v.begin(), v.end());

  int i = 0;
  auto itr = v.begin();
  while (i < m) {
    if(*itr == 0) itr++;
    else {
      *itr -= 1;
      i++;
    }
  }

  if (*itr == 0) itr++;

  printf("%d\n",distance(v.begin(), itr));
}