#pragma GCC optimize(2)

#pragma GCC optimize(3)

#pragma GCC optimize(4)

#include<bits/stdc++.h>

using namespace std;

#define y1 y11

#define fi first

#define se second

#define pi acos(-1.0)

#define LL long long

//#define mp make_pair

#define pb push_back

#define ls rt<<1, l, m

#define rs rt<<1|1, m+1, r

#define ULL unsigned LL

#define pll pair<LL, LL>

#define pli pair<LL, int>

#define pii pair<int, int>

#define piii pair<pii, int>

#define pdd pair<double, double>

#define mem(a, b) memset(a, b, sizeof(a))

#define debug(x) cerr << #x << " = " << x << "\n";

#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

//head

const int N =  + ;

const int INF = 0x3f3f3f3f;

int a[N][N];

struct edge {

    int to, cap, cost, rev;

};

int V;

vector<edge>g[N];

int h[N], dis[N], prevv[N], preve[N];

void add_edge(int u, int v, int cap, int cost) {

    g[u].pb({v, cap, cost, g[v].size()});

    g[v].pb({u, , -cost, g[u].size()-});

}

int min_cost_flow(int s, int t, int f) {

    int res = ;

    mem(h, );

    while(f > ) {

        priority_queue<pii, vector<pii>, greater<pii> > q;

        mem(dis, 0x3f);

        dis[s] = ;

        q.push({, s});

        while(!q.empty()) {

            pii p = q.top();

            q.pop();

            int v = p.se;

            if(dis[v] < p.fi) continue;

            for (int i = ; i < g[v].size(); ++i) {

                edge &e = g[v][i];

                if(e.cap >  && dis[e.to] > dis[v] + e.cost + h[v] - h[e.to]) {

                    dis[e.to] = dis[v] + e.cost + h[v] - h[e.to];

                    prevv[e.to] = v;

                    preve[e.to] = i;

                    q.push({dis[e.to], e.to});

                }

            }

        }

        if(dis[t] == INF) return -;

        for (int v = ; v < V; ++v) h[v] += dis[v];

        int d = f;

        for (int v = t; v != s; v = prevv[v]) d = min(d, g[prevv[v]][preve[v]].cap);

        f -= d;

        res += d*h[t];

        for (int v = t; v != s; v = prevv[v]) {

            edge &e = g[prevv[v]][preve[v]];

            e.cap -= d;

            g[v][e.rev].cap += d;

        }

    }

    return res;

}

int main() {

    int n = ;

    for (int i = ; i <= n; ++i) {

        for (int j = ; j <= n; ++j) {

            scanf("%d", &a[i][j]);

            add_edge(i, j+n, , -a[i][j]);

        }

    }

    int s = , t = n+n+;

    V = t+;

    for (int i = ; i <= n; ++i) add_edge(s, i, , );

    for (int i = ; i <= n; ++i) add_edge(i+n, t, , );

    cout << *n - min_cost_flow(s, t, n);

    return ;

}