#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ldb;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ldb,ldb> pdd;
#define ff(i,a,b) for(int i = a; i <= b; i++)
#define fb(i,b,a) for(int i = b; i >= a; i--)
#define trav(a,x) for(auto& a : x)
#define sz(a) (int)(a).size()
#define fi first
#define se second
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k) print the k-th smallest number in os(0-based)
const int mod = 1000000007;
const ll inf = 1e15 + 5;
const int mxN = 2050;
int n;
int mat[mxN][mxN];
ll dp[mxN][mxN];
pii seg[4 * mxN];
int poz[4 * mxN];
void calc(int v, int tl, int tr){
seg[v] = {tl, tr};
if(tl == tr){
poz[tl] = v;
return;
}
int mid = (tl + tr) / 2;
calc(v * 2, tl, mid); calc(v * 2 + 1, mid + 1, tr);
}
int main(){
cin.tie(0)->sync_with_stdio(0);
cin >> n;
ff(i,0,n - 1)ff(j,0,n - 1)cin >> mat[i][j];
calc(1,0,n - 1);
ff(i,0,n)ff(a,0,n)dp[i][a] = inf;
ff(a,0,n - 1)dp[0][a] = 0;
ff(i,1,n - 1){
int X = 0;
ff(j,0,11){
if((i >> j) & 1){
X = j;
break;
}
}
ff(a,0,n - 1){
int pos = poz[a];
pos >>= X;
int L = seg[pos ^ 1].fi;
int R = seg[pos ^ 1].se;
ff(b,L,R){
dp[i][a] = min(dp[i][a], dp[i - 1][b] + mat[a][b]);
}
}
}
ll rez = inf;
ff(a,0,n - 1)rez = min(rez, dp[n - 1][a]);
cout << rez << '\n';
return 0;
}
/*
// probati bojenje sahovski
*/
