C++
#include "bits/stdc++.h"
using namespace std;
#define pii pair<int,int>
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define ll long long
const int N = 200006;
ll machines[N];
int n;
bool check(ll val,ll target){
ll products = 0;
int cnt=0;
for(int i=0;i<n;i++){
if( machines[i]>val ) return false;
if( products+machines[i]>val ){
products = 0;
cnt++;
}
products+=machines[i];
}
cnt++;
// cout<<cnt<<endl;
return cnt<=target;
}
int main(){
//ifstream cin("test_input.txt");
ll t;
cin>>n>>t;
for(int i=0;i<n;i++)
cin>>machines[i];
ll hi = 2e16;
ll lo = 0;
ll res = 0;
while(lo<=hi){
ll mid = (lo+hi)/2;
// cout<<lo<<" "<<mid<<" "<<hi<<" ";
if( check(mid,t) ){
res = mid;
hi = mid-1;
}else{
lo = mid+1;
}
}
cout<<res;
}