#include <bits/stdc++.h>

using namespace std;

#define N 100005

int n,m,p[N],mx=0;

bool enough(int e){

    if(e<mx) return false;

    int bm=m,be=e;

    for(int i=0;i<n;i++){

        if(be-p[i]<0){

            if(--bm<0) return false;

            be=e;

        }

        be-=p[i];

    }

    return true;

}

int main(){

    int all=0;

    cin>>n>>m;

    for(int i=0;i<n;i++){

        cin>>p[i];

        mx=max(mx,p[i]);

        all+=p[i];

    }

    int t=0;

    if(m==0) cout<<all;

    else

        for(int jump=all/2;jump>0;jump>>=1){

            while(t+jump<all && !enough(t+jump))

                t+=jump;

        }

    cout<<++t;

    return 0;

}