#include <fstream>
#include <algorithm>
#include<cstdio>
using namespace std;

#define dim 50001

int v[dim];
int a[10*dim];
int main()
{
	int n, i, k, j;
	
	ifstream fin("sume.in");
	ofstream fout("sume.out");
	freopen("sume", "r", stdin);
	freopen("sume", "w", stdout);
	
	fin>>n >>k;
	//scanf("%ld", &n);
	//scanf("%ld", &k);
	for(i=1;i<=n;++i)
		fin>>v[i];
	
	
	int f=1;
	for(i=1;i<=n;++i)
	{
		for(j=i;j<=n;++j)
		{
			if(v[i]==v[j])
			{
				a[f]=2*v[i];
				++f;
			}
			else
			{
				a[f]=v[i]+v[j];
				a[f+1]=v[i]+v[j];
				f+=2;
			}
			
		}
	}		
		
	sort(a, a+n*n+1);
	
	
	//printf("%d", a[k]);
	fout<<a[k];
	return 0;
}