#include<stdio.h>
FILE*fin,*fout;
long int v[20001],i,j,n,m,k,p,u,nr,c,min,max;
int main(){

fin=fopen("trans.in","r");
fout=fopen("trans.out","w");
fscanf(fin,"%ld %ld",&n,&k);
for(i=1;i<=n;i++){
fscanf(fin,"%ld",&v[i]);
v[i]=v[i]+v[i-1];
}
p=v[1];
u=v[n];

min=256000001;
while(p<=u){
m=(p+u)/2;
      nr=0;   c=0;
      for(i=1;i<=n;i++){
	while(v[i]-v[c]<=m&&i<=n){i++;}
	nr++;
	c=i-1;i--;


      }
 if(nr==k){max=m;u=m-1;
 if(m<min){min=m;}
 }
 else if(nr>k){p=m+1;}
      else {
	u=m-1;
      }
}
fprintf(fout,"%ld",min);
fclose(fin);
fclose(fout);

return 0;
}