#include<stdio.h>
#define N 16001
long a[N],n,i,k,s[N],x,c,t,j;
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];
for(j=1;j<=s[n];j<<=1);
for(c=0;j;j>>=1)
if(c+j<=s[n])
       {for(i=1,t=x=0;i<=n;)
       if(s[i]-s[t]<=c+j)
               i++;
       else
               t=i-1,x++;
       if(s[n]-s[t]<=c+j)
               x++;
       if(x>k)
               c+=j;}
fprintf(f2,"%ld",c+1);
return 0;}