#include<stdio.h>
#include<memory.h>
#define inf 0x7d00
int a[202][202],c[202][202],i,j,n,m,k,l,p,d[202],t[202],b[40002],s[202];
FILE *in,*out;

int drmin(){
int i,j,p,u,ok;
memset(s,0x0,sizeof(s));
for(i=0;i<=n+1;i++)
 d[i]=inf;
d[0]=0;
p=u=1;b[1]=0;s[0]=1;
while(p<=u){
 i=b[p];
  for(j=0;j<=n+1;j++)
    if(i!=n+1&&c[i][j]==1&&d[j]>d[i]+a[i][j]){
     d[j]=d[i]+a[i][j];
     t[j]=i;
      if(!s[j]){
       b[++u]=j;
       s[j]=1;
      }
    }
 s[i]=0;
 p++;
}
return(d[n+1]);
}

int intoarce(){
int i=n+1;
while(i!=0){
 c[t[i]][i]--;
 c[i][t[i]]++;
 i=t[i];
}
return(0);
}

int main(){
in=fopen("cc.in","rt");
out=fopen("cc.out","wt");
fscanf(in,"%d",&n);
//memset(a,0x7d00,sizeof(a));
//memset(c,0x2,sizeof(c));
m=(n<<1)+1;
for(i=0;i<=m;i++)
  for(j=0;j<=m;j++){
   c[i][j]=2;
   a[i][j]=inf;
  }
for(i=1;i<=n;i++){
 a[0][i]=a[n+i][m]=0;
 a[i][0]=a[m][n+i]=-1;
 c[0][i]=c[n+i][m]=1;
 c[i][0]=c[m][n+i]=0;
  for(j=1;j<=n;j++){
   fscanf(in,"%d",&l);
   a[i][n+j]=l;
   a[n+j][i]=-l;
   c[i][n+j]=1;
   c[n+j][i]=0;
  }
}
n=n<<1;
m=0;
while((l=drmin())!=inf){
 m+=l;
 intoarce();
}
fprintf(out,"%d\n",m);
return(0);
}