#include <stdio.h>

int n,k,i,v[16010];
long min,max,s=0,nr,suma,si,nrj,sol;

int main()
{
	freopen("transport.in","r",stdin);
	freopen("transport.out","w",stdout);
	scanf("%d%d",&n,&k);
	for(i=1;i<=n;i++){
		scanf("%d",&v[i]);
		if(v[i]>s){
			s=v[i];
		}
		max+=v[i];
	}
	min=s;
	while(min<max){
		nr=(min+max)/2;
		nrj=nr;
		si=0;
		i=1;
		while(i<=n){
			si++;
			while(i<=n && v[i]<=nrj){
				nrj-=v[i];
				i++;
			}
			nrj=nr;
		}
		if(si<=k){
			max=nr-1;
			sol=nr;
		}else{
			min=nr+1;
		}
		//printf("%d\n\n",nr);
	}
	printf("%ld",sol-1);
	return 0;
}