#include <bits/stdc++.h>
using namespace std;
const int nx=21;
int n, k, res, dsu[nx], x, cmp;
priority_queue<tuple<int, int, int>, vector<tuple<int, int, int>>, greater<tuple<int, int, int>>> edg;
int find(int x)
{
if (dsu[x]==x) return x;
return dsu[x]=find(dsu[x]);
}
int main()
{
cin.tie(NULL)->sync_with_stdio(false);
cin>>n>>k;
cmp=n;
for (int i=1; i<=n; i++)
{
dsu[i]=i;
for (int j=1; j<=n; j++)
{
cin>>x;
if (i<j) edg.push({x, i, j});
}
}
while (cmp>k)
{
auto [cst, u, v]=edg.top();
edg.pop();
if (find(u)!=find(v)) cmp--, dsu[find(u)]=find(v), res+=cst;
}
cout<<res;
}
