#include <iostream>
#define MAX 100000

using namespace std;

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(){
	cin >> n >> k;
	for( int i = 0; i < n; i++ ) cin >> T[i];
	llong ans = solve();
	cout << ans << endl;
}
