#include <fstream>
using namespace std;

ifstream fin("transport.in");
ofstream fout("transport.out");
const int nmax=16001;
int n, k, i, maxx=-1, v[nmax];
int cb1(int x, int st, int dr) {
	int m, p;
	while(st<=dr) {
		m=(st+dr)/2;
		if(x>=v[m])
			st=m+1, p=m;
		else
			dr=m-1;
	}
	return p;
}
int transp(int c) {
	int k=0, t=0;
	while(k<n) {
		k=cb1(v[k]+c, k+1, n);
		t++;
	}
	return t;
}
int cb2(int k) {
	int st=maxx, dr=v[n], m, p;
	while(st<=dr) {
		m=(st+dr)/2;
		if(k>=transp(m))
			dr=m-1, p=m;
		else
			st=m+1;
	}
	return p;
}
int main()
{
	fin>>n>>k;
	for(i=1; i<=n; i++) {
		fin>>v[i];
		if(v[i]>maxx)
			maxx=v[i];
		v[i]+=v[i-1];
	}
	fout<<cb2(k);
	fin.close();
	fout.close();
	return 0;
}