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

int main(){
	scanf("%d %d", &n, &k);
	for(int i = 0; i<n; i++){
		scanf("%d", &T[i]);
	}
	llong ans = solve();
	printf("%d\n",ans);
}

