#include<stdio.h>
#define N 16001
long a[N],n,i,k,s[N],x,c,t,m;
int main()
{FILE *f1=fopen("transport.in","r"),*f2=fopen("transport.out","w");
fscanf(f1,"%ld%ld",&n,&k);
for(i=1;i<=n;i++)
       {fscanf(f1,"%ld",&a[i]),s[i]=s[i-1]+a[i];
       if(a[i]>m)
              m=a[i];}
c=m;
while(1)
       {for(i=1,t=x=0;i<=n;)
       if(s[i]-s[t]<=c)
               i++;
       else
               t=i-1,x++;
       if(s[n]-s[t]<=c)
               x++;
       if(x==k)
               break;
       else
               if(x<k)
                       c--;
               else
                       c++;}
fprintf(f2,"%ld",c);
return 0;}