#include<stdio.h>
#include<math.h>
#include<iomanip.h>
#define dim 202

typedef struct nod{
        int info;
        nod*urm;
        }*PNOD,NOD;
PNOD l[dim];

int c[dim][dim],cost[dim][dim],f[dim][dim];
int n,m;
int d[dim],t[dim],s[dim];
int flow;
void citire();
void add(int ,int );
int bellman();
void solve();
void afiseaza();
int minimizeaza();
void drum();

int main()
{
     freopen("cc.in","r",stdin);
     freopen("cc.out","w",stdout);
     
     citire();
     solve();
     afiseaza();          
     return 0;
}
void citire()
{
     scanf("%d",&n);
     int i,j,x;
     for(i=1;i<=n;i++)
     {
                      for(j=1;j<=n;j++)
                      {
                                       scanf("%d",&x);
                                       add(i,j+n);
                                       add(j+n,i);
                                       c[i][j+n]=c[j+n][i]=1;
                                       cost[i][j+n]=cost[j+n][i]=x;
                      }
                       
     }
     for(i=1;i<=n;i++)
     {
                      add(0,i);
                      add(i,0);
                      c[0][i]=c[i][0]=1;
                      cost[0][i]=cost[i][0]=0;
     }
     for(i=n+1;i<=n+n;i++)
     {
                          add(i,n+n+1);
                          add(n+n+1,i);
                          c[i][n+n+1]=c[n+n+1][i]=1;
     }                
     
}
void add(int i,int j)
{
     PNOD p=new NOD;
     p->info=j;
     p->urm=l[i];
     l[i]=p;
}
void solve()
{
     while(bellman())
     drum();
}
int bellman()
{
     int i;
     for(i=0;i<=n+n+1;i++)
     {
                          d[i]=2000000;
                          t[i]=0;
     }
     d[0]=0;
     for(i=1;i<=n+n+1;i++)
     if(!minimizeaza())
     break;
     if(d[n+n+1]==2000000)
     return 0;
     return 1;
}
     
int minimizeaza()
{
    int i,j,ok;
    ok=0;
    for(i=0;i<=n+n+1;i++)
      for(PNOD p=l[i];p;p=p->urm)     
      {
               j=p->info;
               if(c[i][j]>f[i][j])
                  if(d[j]>d[i]+cost[i][j])
                  {
                                          d[j]=d[i]+cost[i][j];
                                          t[j]=i;
                                          ok=1;
                                          if(j==n+n+1) return 1;
                  }
                  if(f[j][i])
                    if(d[j]>d[i]-cost[i][j])
                    {
                                            d[j]=d[i]-cost[i][j];
                                            t[j]=-i;
                                            ok=1;
                                            if(j==n+n+1) return 1;
                    }
      }
      return ok;
}
void drum()
{
     int i,j;
     i=n+n+1;
     while(i)
     {
             j=abs(t[i]);
             if(t[j]>=0) f[j][i]++;
             else
                         f[i][j]--;
                       
             i=j;
     }
     flow++;
}
void afiseaza()
{
    int i,j,s=0;
    
    //rintf("%d",flow);
    for(i=1;i<=n;i++)
    {
                     for(j=n+1;j<=n+n;j++)
                     if(f[i][j])
                     s+=cost[i][j];
     }
     printf("%d",s);
}