#include <cstdio>
#include <vector>
#include <algorithm>
#include <queue>
#include <climits>

using namespace std;

const int nmax = 100;

struct Muchie {
    int to, rev, flow, cap, cost;
};

struct Nod {
    int nod, cost;

    bool operator > (Nod other) const {
        return cost > other.cost;
    }
};

int n, src, dest;
vector <Muchie> g[5 + nmax];
int dist[5 + nmax], distdij[5 + nmax], prevnode[5 + nmax], prevedge[5 + nmax], prevflow[5 + nmax];

void bellmanford() {
    fill(dist, dist + dest + 1, INT_MAX);
    queue <int> q;
    q.push(src);
    dist[src] = 0;

    while(!q.empty()) {
        int from = q.front();

        for(int k = 0; k < g[from].size(); ++ k) {
            Muchie& e = g[from][k];

            if(e.flow < e.cap && dist[from] + e.cost < dist[e.to]) {
                dist[e.to] = dist[from] + e.cost;
                q.push(e.to);
            }
        }

        q.pop();
    }
}

bool viz[5 + nmax];
void dijkstra() {
    fill(viz, viz + dest + 1, 0);
    fill(distdij, distdij + dest + 1, INT_MAX);
    priority_queue <Nod, vector<Nod>, greater<Nod>> q;

    q.push({src, 0});
    prevflow[src] = INT_MAX;
    distdij[src] = 0;

    while(!q.empty()) {
        int from = q.top().nod;

        if(viz[from] == 0) {
            viz[from] = 1;
            for(int k = 0; k < g[from].size(); ++ k) {
                Muchie& e = g[from][k];

                int aux = distdij[from] + dist[from] - dist[e.to] + e.cost;
                if(e.flow < e.cap && aux < distdij[e.to]) {
                    distdij[e.to] = aux;
                    q.push({e.to, aux});

                    prevnode[e.to] = from;
                    prevedge[e.to] = k;
                    prevflow[e.to] = min(prevflow[from], e.cap - e.flow);
                }
            }
        }

        q.pop();
    }
}

int mincutflow() {
    int cost = 0;
    bellmanford();
    dijkstra();
    while(distdij[dest] < INT_MAX) {
        int deltaFlow = prevflow[dest];

        for(int i = dest; i != src; i = prevnode[i]) {
            Muchie& e = g[prevnode[i]][prevedge[i]];

            e.flow += deltaFlow;
            g[e.to][e.rev].flow -= deltaFlow;
            cost += deltaFlow * e.cost;
        }

        for(int i = 0; i <= dest; ++ i) {
            dist[i] += distdij[i];
        }
        dijkstra();
    }

    return cost;
}

int main() {
    freopen("cc.in", "r", stdin);
    freopen("cc.out", "w", stdout);

    scanf("%d", &n);
    dest = n + n + 1;

    for(int i = 1; i <= n; ++ i) {
        for(int j = 1; j <= n; ++ j) {
            int x;
            scanf("%d", &x);

            g[i].push_back({j + n, g[j + n].size(), 0, 1, x});
            g[j + n].push_back({i, g[i].size() - 1, 0, 0, -x});
        }
    }

    for(int i = 1; i <= n; ++ i) {
        g[src].push_back({i, g[i].size(), 0, 1, 0});
        g[i].push_back({src, g[src].size() - 1, 0, 0, 0});
    }

    for(int i = 1; i <= n; ++ i) {
        g[i + n].push_back({dest, g[dest].size(), 0, 1, 0});
        g[dest].push_back({i + n, g[i + n].size() - 1, 0, 0, 0});
    }

    printf("%d\n", mincutflow());

    return 0;
}