#include <fstream>
#include <vector>
#include <bitset>
#include <queue>
#include <algorithm>
#include <utility>
#include <string.h>
 
using namespace std;
 
ifstream cin("cc.in");
ofstream cout("cc.out");
 
const int MAXN = 105;
const int oo = (1<<31)-1;
 
typedef vector<int> Graph[MAXN];
typedef vector<int> :: iterator It;
 
Graph G;
int N, So, Si, Qu[MAXN][MAXN], C[MAXN][MAXN];
vector<int> D(MAXN, oo), Act(MAXN), Old(MAXN), Father(MAXN);
priority_queue<pair<int, int> , vector<pair<int, int> > , greater<pair<int, int> > > Q;
 
inline bool Dijkstra() {
    fill(D.begin(), D.end() , oo);
    Q.push(make_pair(0, So));
    D[So] = 0;
    Act[So] = 0;
    for( ; !Q.empty() ; ) {
        int act = Q.top().second;
        int actv = Q.top().first;
        Q.pop();
        if(actv != D[act])  continue;
        for(It it = G[act].begin(), fin = G[act].end() ; it != fin ; ++ it)
            if(Qu[act][*it]) {
                int actual = C[act][*it] + Old[act] - Old[*it];
                if(D[*it] > D[act] + actual ) {
                    Father[*it] = act;
                    D[*it] = D[act] + actual;
                    Act[*it] = Act[act] + C[act][*it];
                    Q.push(make_pair(D[*it], *it));
                }
            }
    }
    Old = Act;
    return D[Si] != oo;
}
 
int main() {
    cin >> N;
    So = 0;
    Si = 2*N + 1;
    for(int i = 1 ; i <= N ; ++ i)
        for(int j = 1; j <= N ; ++ j) {
            int x; cin >> x;   ///distanta de la i la j
            G[i].push_back(N + j);
            G[N + j].push_back(i);
            Qu[i][N+j] = 1;
            C[i][N+j] = x;
            C[N+j][i] = -x;
 
        }
    for(int i = 1 ; i <= N ; ++i) {
        Qu[So][i] = 1;
        Qu[N+i][Si] = 1;
        G[So].push_back(i);
        G[i].push_back(So);
        G[Si].push_back(N+i);
        G[N+i].push_back(Si);
    }
    int MinimumDist = 0;
    for( ; Dijkstra() ; ) {
        int MinFlow = oo;
        for(int i = Si ; i != So ; i = Father[i])
            MinFlow = min(MinFlow, Qu[Father[i]][i]);
        for(int i = Si ; i != So ; i = Father[i])
            Qu[Father[i]][i] -= MinFlow,
            Qu[i][Father[i]] += MinFlow;
        MinimumDist += MinFlow * Act[Si];
    }
    cout << MinimumDist << "\n";
    cin.close();
    cout.close();
    return 0;
}