#include<cstdio>
#include<vector>
#include<queue>
using namespace std;

FILE *fin = freopen("cc.in", "r", stdin);
FILE *fout = freopen("cc.out", "w", stdout);

const int INF = 0x7fffffff;
const int NMax = 102;
int N, S, D, sol;
int carry[NMax][NMax], cost[NMax][NMax], dist[NMax], fromWhere[NMax];
bool used[NMax];
vector < int > v[NMax];
queue < int > q;

inline bool BellmanFord(){

    for (int i = S; i <= D; i++){

        dist[i] = INF;
        used[i] = 0;
    }

    q.push(S);
    used[S] = 1;
    dist[S] = 0;

    while (!q.empty()){

        int node = q.front();
        q.pop();
        used[node] = 0;

        vector < int > :: iterator it;
        for (it = v[node].begin(); it != v[node].end(); it ++)
        if (carry[node][*it] > 0 && dist[*it] > dist[node] + cost[node][*it]){

            dist[*it] = dist[node] + cost[node][*it];
            fromWhere[*it] = node;
            if (!used[*it]){

                used[*it] = 1;
                q.push(*it);
            }
        }
    }

    if (dist[D] != INF){

        for (int i = D; i != S; i = fromWhere[i]){

            carry[fromWhere[i]][i] --;
            carry[i][fromWhere[i]] ++;

            sol += cost[fromWhere[i]][i];
        }
        return 1;
    }

    return 0;
}

int main(){

    scanf("%d", &N);
    S = 0;
    D = 2 * N + 1;

    for (int i = 1; i <= N; i++)
    for (int j = 1; j <= N; j++){

        scanf("%d", &cost[i][j + N]);
        cost[j + N][i] = - cost[i][j + N];
        carry[i][j + N] = 1;

        v[i].push_back(j + N);
        v[j + N].push_back(i);
    }

    for (int i = 1; i <= N; i++){

        v[S].push_back(i);
        v[i].push_back(S);
        carry[S][i] = 1;
    }

    for (int i = N + 1; i <= N + N; i++){

        v[D].push_back(i);
        v[i].push_back(D);
        carry[i][D] = 1;
    }

    while (BellmanFord());

    printf("%d\n", sol);
}