#include<cstdio>
int v[16201];
int main()
{
 int n,k,max,s,e,i,q,st,dr,m,p,t;
 freopen("transport.in","r",stdin);
 freopen("transport.out","w",stdout);
 scanf("%d%d",&n,&k);
 max=s=0;
 for(i=1;i<=n;i++)
    {
     scanf("%d",&v[i]);
     if(v[i]>max)
        max=v[i];
     s+=v[i];
    }
 st=1;
 dr=s;
 e=0;
 while(st<=dr)
      {
       m=(st+dr)/2;
       p=max+m-1;
       t=0;
       for(i=1;i<=n;i++)
          {
           s=0;
           while(s+v[i]<=p && i<=n)
                {
                 s+=v[i];
                 i++;
                }
           t++;
           i--;
          }
       if(t<=k)
          {
           e=max+m-1;
           dr=m-1;
          }
       else
           st=m+1;
      }
 printf("%d\n",e);
return 0;
}