#include <bits/stdc++.h>

using namespace std;
ifstream f("cc.in");
ofstream g("cc.out");
priority_queue <pair <int,int> , vector <pair <int,int>> , greater <pair <int,int>>> h;
int distanta[105],tata[105],cost[105][105],cap[105][105],flux[105][105];
vector <int> v[105];
int n,i,j,sursa,destinatie;
bool ok (int sursa,int destinatie)
{
    int i;
    for (i=sursa;i<=destinatie;i++)
    {
        distanta[i]=1e9;
    }
    tata[sursa]=0;
    distanta[sursa]=0;
    h.push({distanta[sursa],sursa});
    while (!h.empty())
    {
        while (!h.empty()&&distanta[h.top().second]!=h.top().first)
        {
            h.pop();
        }
        if (h.empty())
        {
            break;
        }
        int acum = h.top().second;
        h.pop();
        for (int i=0;i<v[acum].size();i++)
        {
            int nod = v[acum][i];
            if (cap[acum][nod]>flux[acum][nod])
            {
                if (distanta[nod]>distanta[acum]+cost[acum][nod])
                {
                    tata[nod]=acum;
                    distanta[nod]=distanta[acum]+cost[acum][nod];
                    h.push({distanta[nod],nod});
                }
            }
        }
    }
    if (distanta[destinatie]==1e9)
    {
        return 0;
    }
    return 1;
}
int main()
{
    f>>n;
    for (i=1;i<=n;i++)
    {
        for (j=1;j<=n;j++)
        {
            f>> cost[i][n+j];
            cost[n+j][i] = -cost[i][n+j];
            cap[i][n+j]=1;
            v[i].push_back(n+j);
            v[n+j].push_back(i);
        }
    }
    sursa = 0 ;
    destinatie = 2*n+1;
    for (i=1;i<=n;i++)
    {
        cap[0][i]=1;
        v[0].push_back(i);
        v[i].push_back(0);
    }
    for (i=1;i<=n;i++)
    {
        cap[n+i][destinatie] = 1;
        v[n+i].push_back(destinatie);
        v[destinatie].push_back(n+i);
    }
    for (i=1;i<=destinatie;i++)
    {
        distanta[i]=1e9;
    }
    distanta[sursa]=0;
    h.push({distanta[sursa],sursa});
    while (!h.empty())
    {
        while (!h.empty()&&distanta[h.top().second]!=h.top().first)
        {
            h.pop();
        }
        if (h.empty())
        {
            break;
        }
        int acum = h.top().second;
        h.pop();
        for (int i=0;i<v[acum].size();i++)
        {
            int nod = v[acum][i];
            if (cap[acum][nod]>flux[acum][nod])
            {
                if (distanta[nod]>distanta[acum]+cost[acum][nod])
                {
                    distanta[nod]=distanta[acum]+cost[acum][nod];
                    h.push({distanta[nod],nod});
                }
            }
        }
    }
    long long solfin =0;
    while (ok(sursa,destinatie))
    {
        int nod = destinatie;
        int sal = cap[tata[nod]][nod]-flux[tata[nod]][nod];
        while (nod!=sursa)
        {
            sal = min (sal, cap[tata[nod]][nod]-flux[tata[nod]][nod]);
            nod=tata[nod];
        }
        solfin =solfin +1LL*sal*distanta[destinatie];
        nod = destinatie;
        while (nod!=sursa)
        {
            flux[tata[nod]][nod]+=sal;
            flux[nod][tata[nod]]-=sal;
            nod=tata[nod];
        }
    }
    g<<solfin;
    return 0;
}