#include<iostream>
#include<cstdio>
#include<cmath>
#include<algorithm>
#include<stack>
#include<queue>
#include<cstring>
#include<deque>
#define itn int
#define xlm mylove
using namespace std;
int n,k,a[100001];long long s=0;int Max=-1;int ans;
inline void readln(){
	freopen("seqa.in","r",stdin);
	freopen("seqa.out","w",stdout);
	scanf("%d%d",&n,&k);
	for (int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		s+=a[i];
		Max=max(Max,a[i]);
	}
}
inline bool check(int x){
	int sum=0,cnt=1;
	for(int i=1;i<=n;i++){
		sum+=a[i];
		if(sum>x) {cnt++;sum=a[i];}
	}
	if (cnt<=k) return 1;
	else return 0;
}
inline void work(){
	int l=Max,r=s;
	while (l<=r){
		int mid=(l+r)>>1;
		if (check(mid)) r=mid-1;
		else l=mid+1;
	}
	ans=l;
}

int Main(){
	readln();
	work();
	printf("%d",ans);
	return 0;
}
int main(){;}
int mylove=Main();