#include<cstdio>
#include<vector>
#include<queue>
#define INF 2000000000
using namespace std;
vector<int>L[1010];
queue<int>q;
int n,m,e,i,j,a,b,aa,s,d,ss,sss,v[1010],x[611][611],c[611][611],M[611][611],D[1010],w[611][611],t[1010];
FILE *f,*g;
int bf(){
    for(i=1;i<=d;i++){
        v[i]=t[i]=0;
        D[i]=INF;
    }
    D[s]=0;
    q.push(s);
    t[s]=-1;
    while(!q.empty()){
        a=q.front();
        q.pop();
        v[a]=0;
        for(int i=0;i<L[a].size();i++){
            b=L[a][i];
            if( D[b] > D[a] + x[a][b] && c[a][b] > w[a][b] ){
                D[b] = D[a] + x[a][b];
                t[b]=a;
                if( v[b] == 0 ){
                    q.push(b);
                    v[b]=1;
                }
            }
        }
    }
    return D[d]!=INF;
}
int main(){
    f=fopen("cc.in","r");
    g=fopen("cc.out","w");
    fscanf(f,"%d",&n);
    for(i=1;i<=n;i++){
        for(j=1;j<=n;j++){
            fscanf(f,"%d",&a);
            L[i].push_back(j+n);
            L[j+n].push_back(i);
            c[i][j+n]=1;
            x[i][j+n]=a;
            x[j+n][i]=-a;
        }
    }
    s=0;
    d=2*n+1;
    for(i=1;i<=n;i++){
        L[s].push_back(i);
        L[i].push_back(s);
        c[s][i]=1;
    }
    for(i=1;i<=n;i++){
        L[d].push_back(i+n);
        L[i+n].push_back(d);
        c[i+n][d]=1;
    }
    while(bf()){
        a=t[d];
        aa=INF;
        while( t[a]!=-1 ){
            if( aa > c[ t[a] ][a] - w[ t[a] ][a] )
                aa = c[ t[a] ][a] - w[ t[a] ][a];
            a=t[a];
        }
        a=d;
        while( t[a]!=-1 ){
            w[ t[a] ][a] += aa;
            w[a][ t[a] ] -= aa;
            a=t[a];
        }
        ss += aa;
        sss += aa * D[d];
    }
    fprintf(g,"%d",sss);
    fclose(f);
    fclose(g);
    return 0;
}