#include<stdio.h>
#define MAX 100000
typedef long long llong;
int n,k;
llong T[MAX];

int check(llong P){
	int i=0;
	for(int j=0; j<k; j++){
		llong s=0;
		while(s + T[i]<=P)
		{
			s+=T[i];
			i++;
			if(i==n){return n;}
		}
	}
	return i;
}
int solve(void){
	llong left=0;
	llong right =100000*10000;
	llong mid;
	while(right-left>1){
		mid=(right+left)/2;
		int v=check(mid);
		if (v>=n) right=mid;
		else left=mid;
	}
	return right;
}
int main(void){
	int i;
	scanf("%d", &n);
	scanf("%d", &k);
	for(i=0; i<n; i++){
		scanf("%d", &T[i]);
	}
	llong ans=solve();
	printf("%d\n",ans);
	return 0;
}
