#include <iostream>
#include <fstream>
using namespace std;

int main()
{
   ifstream fin("transport.in");
   ofstream fout("transport.out");
   int N,K,i,v[16001],t,s=0,a=0;
   fin>>N>>K;
   for(i=1;i<=N;i++)
   {
       fin>>v[i];
       s=s+v[i];
   }
   t=s/K;
   for(i=1;i<=N;i++)
   {
        if(t!=0)
        {
           t=t-v[i];
        }
        else
        {
           t=s/K; 
           a++;
        }
   }
   if(a<=K)
      fout<<t;
    else
      fout<<t+a-K;
   fin.close();
   fout.close();
   return 0;
}