#include <stdio.h>
#define MAX 100000

int n,k;
long long T[MAX];
int check(long long P);
int solve();

int main(void){
	scanf("%d %d",&n,&k);
	for(int i; i < n; i++){
	scanf("%d", &T[i]);
	}
	long long ans = solve();
	printf("%d\n",ans);


}

int check(long long P){
	int i = 0;
	for(int j = 0;j < k ;j++){
	long long s=0;
		while( s + T[i] <= P){
		s += T[i];
		i++;
		if(i == n) return n;
		}
	}
	return i;
}

int solve(){
	long long left = 0;
	long long right = 100000 * 10000;
	long long mid;
	while(right - left > 1){
	mid = (left + right) / 2;
	int v = check(mid);
	if(v >= n) right = mid;
	else left = mid;
	}
	return right;
}
