#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> ii;
typedef vector<ll> vi;
typedef vector<vi> vvi;
typedef vector<ii> vii;

#define x first
#define y second
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(), (v).end()

void run() {
	ll n;
	cin >> n;
	vi A(n, 0);
	for (ll i = 0; i < n; i++) {
		for (ll j = 0; j < n; j++) {
			ll c;
			cin >> c;
			A[i] += c;
		}
	}
	sort(all(A));
	ll res = 0;
	for (ll i = 0; i < n; i++) {
		if (2*i < n) res -= A[i];
		else res += A[i];
	}
	cout << res/2 << endl;
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(0);
    run();
    return 0;
}