https://ac.nowcoder.com/acm/contest/882/F
#include <iostream>
#include <cstring>
#include <algorithm>
#include <cstdio>
#include <map>
using namespace std;
#define sfi(x) scanf("%d",&x)
#define sfc(x) scanf("%c",x)
#define sfl(x) scanf("%lld",&x)
#define sfs(x) scanf("%s",x)
#define fl() printf("flag!\n")
#define INF 0x3f3f3f3f
#define ll long long
#define mem(x,y) memset(x,y,sizeof(x))
#define FAST_IO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0)
const int maxn=1e3+9;
const int mod=1e9+7;
ll a[30][30];
ll sum[30];
vector<int>v;
int n;
ll ans=0;
void dfs(int pos,ll tot)
{
if(pos>2*n) return ;
if(v.size()==n)
{
ans=max(ans,tot);
return ;
}
if(n<pos-v.size()) return ;
ll k=0;
for(int i=0;i<v.size();i++) k+=2*a[pos][v[i]];
v.push_back(pos);
dfs(pos+1,tot+sum[pos]-k);
v.pop_back();
dfs(pos+1,tot);
}
int main()
{
//FAST_IO;
scanf("%d",&n);
for(int i=1;i<=n*2;i++)
{
for(int j=1;j<=2*n;j++)
{
sfl(a[i][j]);
sum[i]+=a[i][j];
}
}
dfs(1,0);
printf("%lld\n",ans);
return 0;
}