#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,popcnt,sse4,abm")
#include <bits/stdc++.h>
using namespace std;
#ifdef WAIMAI
#define debug(HEHE...) cout << "[" << #HEHE << "] : ", dout(HEHE)
void dout() {cout << '\n';}
template<typename T, typename...U>
void dout(T t, U...u) {cout << t << (sizeof...(u) ? ", " : ""), dout(u...);}
#else
#define debug(...) 7122
#endif
#define ll long long
#define Waimai ios::sync_with_stdio(false), cin.tie(0)
#define FOR(x,a,b) for (int x = a, I = b; x <= I; x++)
#define pb emplace_back
#define F first
#define S second
const ll INF = 1e18;
const int SIZE = 2100;
int n;
int a[SIZE][SIZE];
ll dp[2][SIZE];
void solve() {
cin >> n;
FOR (i, 0, n - 1) FOR (j, 0, n - 1) cin >> a[i][j];
FOR (i, 1, n - 1) {
int f = (i + 1) & 1, b = i & -i;
fill(dp[f], dp[f] + n, INF);
FOR (j, 0, n - 1) {
int s = (j ^ b) & (~(b - 1));
FOR (k, s, s + b - 1) dp[f][k] = min(dp[f][k], dp[!f][j] + a[j][k]);
}
}
cout << *min_element(dp[n & 1], dp[n & 1] + n) << '\n';
}
int main() {
Waimai;
solve();
}
