#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int n,m,M[100001],r=0,l=0,ans;
int solve(int x){
	int ss=0,sum=0;
	for(int i=1;i<=n;i++){
		if(M[i]+sum>x){
			ss++;
			sum=M[i];
		}
		else
		sum+=M[i];
		if(ss>=m)
			return 0;
	}
	return 1;
}
int main(){
	freopen("expense.in","r",stdin);
	freopen("expense.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++){
		scanf("%d",&M[i]);
		r+=M[i];l=max(l,M[i]);
	}
	while(l<=r){
		int mid=(l+r)>>1;
		if(solve(mid)){
			r=mid-1;
			ans=mid;
		}
		else
			l=mid+1;
	}
	cout<<ans;
	return 0;
}