rt，link. 人已经懵了。

#include <iostream>
#include <ctype.h>
#include <cstring>
#include <string>
#include <cstdio>
#include <vector>
#include <cmath>

using namespace std ;

typedef int lint ;

const lint INF = 0x7fffffff ;
const lint MAXN = 2e1 + 5 ;
const lint MAXM = pow(2, MAXN) + 5 ;
const lint MAXS = 1e3 + 5 ; 

lint s ;
lint n, m ;
lint ans = INF ;

vector<vector<lint>> dp(MAXM, vector<lint>(MAXN)) ; 
vector<vector<lint>> rem(MAXN, vector<lint>(MAXN)) ; 

inline void read(lint &x) {
	char c ;
	bool b = true ;
	for (c = getchar() ; !isdigit(c) ; c = getchar()) 
		if(c == '-') b = false ;
	for (x = 0 ; isdigit(c) ; c = getchar())
		x = x * 10 + c - '0' ;
	if(b == false) x *= -1 ;
	return ;
}

signed main ( ) {
	
	cin >> n ;
	m = pow(2, n) - 1 ;
	for (lint i = 1 ; i <= n ; i ++)
		for (lint j = 1 ; j <= 1 ; j ++)
			read(rem[i][j]) ;
	
	for (lint i = 1 ; i <= m ; i += 2)
		for (lint j = 1 ; j <= n ; j ++)
			dp[i][j] = -1 ;
	dp[1][1] = 0 ;
	
	for (lint i = 3, l = 2, p = 4 ; i <= m ; i += 2) {
		if(i > p)
			p = p << 1 , l ++ ;
		for (lint j = 2 ; j <= l ; j ++) {
			if(((i >> j - 1) & 1) == 1) {
				s = (i ^ (1 << j - 1)) ; // 状态转移（求 s）
				// 维护dp数组
				for (int k = 1 ; k < j ; k ++)
					dp[i][j] = min(dp[i][j], dp[s][k] + rem[k][j]) ;
				for (int k = j + 1 ; k <= l ; k ++)
					dp[i][j] = min(dp[i][j], dp[s][k] + rem[k][j]) ;
			}
		}
	}
	
	for (int i = 2 ; i <= n ; i ++) 
		ans == min(dp[s][i], ans) ;
	
	cout << ans << '\n' ;
	
	return 0 ;
}