#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={-1,0,1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
ll n;
ll solve(vvl mat,ll m){//matに対してm個開ける
    ll ans=INF;
    rep(bit,1<<n){
        if(__builtin_popcount(bit)+n<m)continue;
        vvl g=mat;
        ll cost=0,need=0;
        rep(i,n){
            if(bit&(1<<i)){
                rep(j,n){
                    cost+=g[i][j];
                    g[i][j]=0;
                }
                need++;
            }
        }
        /*rep(i,n){
            rep(j,n){
                cout << g[i][j] <<" ";
            }
            cout << endl;
        }
        cout << cost <<endl;*/
        vl rem(n);
        rep(i,n){
            rep(j,n){
                rem[i]+=g[j][i];
            }
        }
        sort(all(rem));
        rep(i,m-need)cost+=rem[i];
        chmin(ans,cost);
    }
    return ans;
}

int main(){
    ll m;cin >> n >>m;
    vvl mat(n,vl(n));
    rep(i,n)rep(j,n)cin >> mat[i][j];
    ll p=solve(mat,m);
    vvl g=mat,gg=mat;
    ll ret=0;
    rep(i,n){
        ret+=g[i][i];
        g[i][i]=0;
    }
    chmin(p,solve(g,m-1)+ret);
    ret=0;
    rep(i,n){
        ret+=gg[i][n-i-1];
        gg[i][n-i-1]=0;
    }
    chmin(p,solve(gg,m-1)+ret);
    ret=0;
    rep(i,n){
        ret+=mat[i][i];
        mat[i][i]=0;
        ret+=mat[i][n-i-1];
        mat[i][n-i-1]=0;
    }
    chmin(p,solve(mat,m-2)+ret);
    cout << p <<endl;
}