#include<bits/stdc++.h>
#define ll			long long
#define rep(i,a,b)	for(ll i=a;i<b;i++)
#define vi			vector<ll>
#define pii			pair<int,int>
#define hell		1000000007
#define F 			first
#define S   		second
#define pb			push_back
using namespace std;
#define N           505
ll dp[N][N],a[N][N];
ll n,ps;

ll check(ll i,ll j)
{
	return ((ps-i+n)%n+(j-ps+n)%n==(j-i+n)%n);
}

ll fun(ll i,ll j)
{
	if(i==j)
		return 0;
	if(dp[i][j]!=-1)
		return dp[i][j];
	if(check(i,j))
	{
		dp[i][j]=min(fun((i-1+n)%n,j)+a[(i-1+n)%n][j],fun(i,(j+1)%n)+a[i][(j+1)%n]);
	}
	else
	{
		dp[i][j]=min(fun((i+1+n)%n,j)+a[(i+1+n)%n][j],fun(i,(j-1+n)%n)+a[i][(j-1+n)%n]);
	}
	return dp[i][j];
}

void solve()
{
	cin>>n;
	rep(i,0,n)
	{
		rep(j,0,n)
		{
			cin>>a[i][j];
		}
	}
	rep(i,0,n)
	{
		rep(j,0,n)
		dp[i][j]=-1;
	}
	ll mn=hell;
	rep(i,0,n)
	{
		ps=i;
		mn=min(mn,fun((i-1+n)%n,(i+1)%n));
	}
	cout<<mn<<endl;
}


int main()
{
	int TESTS=1;
	// cin>>TESTS;
	while(TESTS--)
		solve();
	return 0;
}