#include <fstream>
using namespace std;
fstream f("transport.in",ios::in);
fstream g("transport.out",ios::out);
long n,k,i,a[16000],nr,s1,s[16000],m,l;
long long su;
int main()
{ f>>n>>k;
 for (i=1;i<=n;i++)
 {f>>a[i];su=su+a[i];}
  nr=su/k;
   for(i=1;i<=k;i++)
    while(s[i]<nr && l<=n)
     {s[i]=s[i]+a[l];
     l++;}
  m=s[1];
   for(i=2;i<=k;i++)
     if(s[i]>m)
      m=s[i];
     g<<m;
  return 0;
}