#include <stdio.h>
#include <queue>
#include <vector>
#define pb push_back
#define NMAX 205
#define INF 1000000000
using namespace std;
int n,A[NMAX][NMAX],rez,ok,sursa,dest,F[NMAX][NMAX],C[NMAX][NMAX],dist[NMAX],dad[NMAX];
vector <int> B[NMAX],cost[NMAX];
char in[NMAX];
queue <int> Q;
inline int min(int x,int y)
{
	return x<y ? x : y;
}
int bford()
{
	int i,nod,vec;
	for (i=1; i<=dest; i++)
		dist[i]=INF;
	Q.push(sursa); in[sursa]=1;
	while (!Q.empty())
	{
		nod=Q.front();
		in[nod]=0;
		Q.pop();
		for (i=0; i<B[nod].size(); i++)
		{
			vec=B[nod][i];
			if (F[nod][vec]==C[nod][vec] || dist[vec]<=dist[nod]+cost[nod][i])
				continue ;
			dad[vec]=nod;
			dist[vec]=dist[nod]+cost[nod][i];
			if (!in[vec])
				Q.push(vec);
		}
	}
	if (dist[dest]!=INF)
	{
		ok=1;
		int val=INF;
		for (i=dest; i!=sursa; i=dad[i])
			val=min(val,C[dad[i]][i]-F[dad[i]][i]);
		for (i=dest; i!=sursa; i=dad[i])
		{
			F[dad[i]][i]+=val;
			F[i][dad[i]]-=val;
		}
		return val*dist[dest];
	}
	return 0;
}
int main()
{
	freopen("cc.in","r",stdin);
	freopen("cc.out","w",stdout);
	scanf("%d",&n);
	int i,j;
	for (i=1; i<=n; i++)
		for (j=1; j<=n; j++)
			scanf("%d",&A[i][j]);
	sursa=0; dest=2*n+1;
	for (i=1; i<=n; i++)
	{
		B[sursa].pb(i); cost[sursa].pb(0); B[i].pb(sursa); cost[i].pb(0);
		C[sursa][i]=1; 
		B[i+n].pb(dest); cost[i+n].pb(0); B[dest].pb(i+n); cost[dest].pb(0);
		C[i+n][dest]=1;
		for (j=1; j<=n; j++)
		{
			B[i].pb(j+n); cost[i].pb(A[i][j]); B[j+n].pb(i); cost[j+n].pb(-A[i][j]);
			C[i][j+n]=1;
		}
	}
	ok=1;
	while (ok)
	{
		ok=0;
		rez+=bford();
	}
	printf("%d\n",rez);
	return 0;
}