#include <bits/stdc++.h>
#define NMAX 109
#define INF 99999999
using namespace std;
ifstream fin("cc.in");
ofstream fout("cc.out");
vector<int>g[NMAX];
int n,m;
void citire();
int cost[NMAX][NMAX];
int c[NMAX][NMAX];
int d[NMAX];
int then[NMAX];
int now[NMAX];
int p[NMAX];
int start,dest;
priority_queue< pair<int,int>, vector<pair<int,int> >, greater< pair<int,int> > >H;

int sol;
bool djk();

void bellman();
int main()
{citire();
bellman();
 while(djk());
 fout<<sol;
    return 0;
}
void citire()
{
 fin>>n;
 int i,j;
 start=0;dest=2*n;


 for(i=1;i<=n;i++)
    for(j=1;j<=n;j++)
        {int x;
            fin>>x;
            cost[i][n+j]=x;
            cost[n+j][i]=-x;
            c[i][n+j]=1;
            g[i].push_back(j+n);
            g[j+n].push_back(i);

        }
 for(i=1;i<=n;i++)
    {
     g[start].push_back(i);
     g[i].push_back(start);

     c[start][i]=1;
     g[i+n].push_back(dest);
     g[dest].push_back(i+n);

     c[i+n][dest]=1;

    }
}
bool djk()
{
 int i;
 for(i=0;i<=dest;i++)
      d[i]=INF;
d[start]=0;
H.push({0,start});
now[start]=0;
while(!H.empty())
    {
     int act=H.top().second;
     int costact=H.top().first;
     H.pop();
     if(costact!=d[act])
         continue;
     for(int i=0;i<g[act].size();i++)
        {
         int vec=g[act][i];
         if(c[act][vec])
            {
            int now_d=d[act]+cost[act][vec]+then[act]-then[vec];
            if(now_d< d[vec])
                {
                 d[vec]=now_d;
                 now[vec]=now[act]+cost[act][vec];
                 H.push({ now_d,vec });
                 p[vec]=act;
                }
            }
        }
    }
 if(d[dest]==INF)
    return 0;
 int ct;
 int minim=INF;
 int costact=0;
 for(ct=dest;ct!=start;ct=p[ct])
    {
      minim=min(minim, c[p[ct]][ct]);
      costact+=cost[ p[ct] ][ct];
    }
 for(ct=dest;ct!=start;ct=p[ct])
    {
     c[p[ct]][ct]-=minim;
    }
  for(ct=start;ct<=dest;ct++)
     then[ct]=now[ct];

  sol+=now[dest];
  return 1;

}
void bellman(){
    for(int i=1;i<=dest;i++)
        then[i]=INF;
    then[start]=0;
    H.push({0,start});
    while(!H.empty())
        {
        int  act=H.top().second;
        int  costact=H.top().first;

        H.pop();
       if(costact!=then[act])continue;

        for(int i=0;i<g[act].size();i++)
            {
             int vec=g[act][i];
            if(c[act][vec])
                {
                 if(then[vec]>then[act]+cost[act][vec])
                    {then[vec]=then[act]+cost[act][vec];
                    H.push({then[vec],vec});
                    }
                }
            }
        }

    }