#include<cstdio>

#include<cstdlib>

#include<cstring>

#include<iostream>

#include<algorithm>

using namespace std;

const int maxn=;

int h[maxn];

int main()

{

     int i,j,n,k,ans=;

     scanf("%d",&n);

     for(i=;i<=n;i++)

      for(j=;j<=n;j++){

        scanf("%d",&k);

        h[j]+=k;

     }

     sort(h+,h+n+);

     for(i=;i<n;i+=){

            if(h[i]<=&&h[i+]<=)      ans=ans-h[i]-h[i+];

            else if(h[i]>=&&h[i+]>=) ans=ans+h[i]+h[i+];

            else if(h[i]<=&&h[i+]>=) ans=ans+max(h[i+]+h[i],-h[i]-h[i+]);

     }

     for(;i<=n;i++) ans+=h[i];

     printf("%d\n",ans);

     return ;

}