#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;
}

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