#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(a) (a).begin(), (a).end()
#define fillchar(a, x) memset(a, x, sizeof(a))
#define huan printf("\n")
#define debug(a,b) cout<<a<<" "<<b<<" "<<endl
#define ffread(a) fastIO::read(a)
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const int N = 310;
const int INF = 0x3f3f3f3f;
int nx,ny;
int g[N][N];//二分图描述 11
int linker[N],lx[N],ly[N];//y 中各点匹配状态，x,y 中的点标号
 int slack[N];
bool visx[N],visy[N];
bool DFS(int x)
{
     visx[x] = true;
     for(int y = 0; y < ny; y++)
    {
         if(visy[y])
            continue;
         int tmp = lx[x] + ly[y] - g[x][y];
         if(tmp == 0)
        {
             visy[y] = true;
             if(linker[y] == -1 || DFS(linker[y]))
            {
                 linker[y] = x;
                return true;

            }

        }
         else if(slack[y] > tmp)
             slack[y] = tmp;
    }
     return false;
}
int KM()
{
    memset(linker,-1,sizeof(linker));
    memset(ly,0,sizeof(ly));
    for(int i = 0; i < nx; i++)
    {
        lx[i] = -INF;
        for(int j = 0; j < ny; j++)
            if(g[i][j] > lx[i])
                lx[i] = g[i][j];
    }
    for(int x = 0; x < nx; x++)
    {
        for(int i = 0; i < ny; i++)
            slack[i] = INF;
        while(true)
        {
            memset(visx,false,sizeof(visx));
            memset(visy,false,sizeof(visy));
            if(DFS(x))
                break;
            int d = INF;
            for(int i = 0; i < ny; i++)
                if(!visy[i] && d > slack[i])
                    d = slack[i];
            for(int i = 0; i < nx; i++)
                if(visx[i])
                    lx[i] -= d;
            for(int i = 0; i < ny; i++)
            {
                if(visy[i])
                    ly[i] += d;
                else
                    slack[i] -= d;
            }
        }
    }
    int res = 0;
    for(int i = 0; i < ny; i++)
        if(linker[i] != -1)
            res += g[linker[i]][i];
    return res;
}
int main()
{
    int n;
    while(scanf("%d",&n) == 1)
    {
        for(int i = 0; i < n; i++)
            for(int j = 0; j < n; j++)
                scanf("%d",&g[i][j]);
        nx = ny = n;
        printf("%d\n",KM());
    }
    return 0;
}