#include <fstream>
using namespace std;
ifstream in("transport.in"); ofstream out("transport.out");
long saltele[16001], af = 922337203685477580;
int main(){
    long s = 0;
    int n, k, maxx = -1;
    in >> n >> k;
    for(int i = 1; i <= n; i++){
        in >> saltele[i]; s+= saltele[i];
        if(saltele[i] > maxx) maxx = saltele[i];
    }
    long st = maxx, dr = s;
    while(st <= dr){
        long kc = 1, v = (st + dr) / 2;
        for(int i = 1; i <= n; i++){
            if(v - saltele[i] >= 0) v -= saltele[i];
            else kc++, v = (st + dr) / 2, i--;
        }
        if(kc <= k){
            if((st + dr) / 2 < af) af = (st + dr) / 2;
            dr = (st + dr) / 2 - 1;
        }
        else{
            st = (st + dr) / 2 + 1;
        }
    }
    out << af;
    in.close(); out.close();
    return 0;
}