#include <cstdio>  
#include <cstring>  
#include <vector>  
#include <queue>  
using namespace std;  
  
#define inf 0x3f3f3f3f  
  
const int maxn = 2 * 102;  
  
int n;  
int f[maxn][maxn], c[maxn][maxn], cost[maxn][maxn];  
vector<int> g[maxn];  
  
int inq[maxn], d[maxn], p[maxn];  
  
int S, D;  
  
void read()  
{  
    scanf("%d", &n);  
    S = 0; D = 2 * n + 1;  
    for (int i = 1; i <= n; ++i)  
    for (int j = 1; j <= n; ++j)  
    {  
        int x; scanf("%d", &x);   
        g[i].push_back(j + n);  
        g[j + n].push_back(i);  
        cost[i][j + n] = x;  
        cost[j + n][i] = -x;  
        c[i][j + n] = 1;  
    }  
    for (int i = 1; i <= n; ++i)  
    {  
    g[0].push_back(i); g[i].push_back(0);  
    c[0][i] = 1;  
  
    g[i + n].push_back(D); g[D].push_back(i + n);  
    c[i + n][D] = 1;  
    }  
}  
  
int ok = 1;  
  
int bf()  
{  
    memset(d, 0x3f, sizeof(d));  
    memset(inq, 0, sizeof(inq));  
    queue<int> Q;  
    Q.push(S); d[S] = 0;  
  
    while (!Q.empty())  
    {  
    int akt = Q.front(); Q.pop();  
    for (int i = 0; i < g[akt].size(); ++i)  
    {  
        int next = g[akt][i];  
        if (c[akt][next] - f[akt][next] == 0) continue;  
  
        if (d[next] > d[akt] + cost[akt][next])  
        {  
        d[next] = d[akt] + cost[akt][next];  
        p[next] = akt;  
        if (!inq[next])  
        {  
            Q.push(next);  
            inq[next] = 1;  
        }  
        }  
    }  
    inq[akt] = 0;  
    }  
  
    if (d[D] != inf)  
    {  
    ok = 1;  
    int minn = inf;  
    for (int i = D; i != 0; i = p[i])  
        minn = min(minn, c[p[i]][i] - f[p[i]][i]);  
    for (int i = D; i != 0; i = p[i])  
    {  
        f[p[i]][i] += minn;   
        f[i][p[i]] -= minn;  
    }  
  
    return minn * d[D];  
    }  
  
    return 0;  
}  
  
void flux()  
{  
    int res = 0;  
    while (ok)   
    {  
    ok = 0;  
    res += bf();  
    }   
    printf("%d\n", res);  
}  
  
int main()  
{  
    freopen("cc.in","r",stdin);  
    freopen("cc.out","w",stdout);  
  
    read();  
    flux();  
  
    return 0;  
}