using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("4");
            WillReturn.Add("-1 16 15 38");
            WillReturn.Add("16 -1 22 17");
            WillReturn.Add("15 22 -1 19");
            WillReturn.Add("38 17 19 -1");
            //60
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("6");
            WillReturn.Add("-1 14 29 35 39 8");
            WillReturn.Add("14 -1 35 41 34 3");
            WillReturn.Add("29 35 -1 14 21 21");
            WillReturn.Add("35 41 14 -1 12 42");
            WillReturn.Add("39 34 21 12 -1 28");
            WillReturn.Add("8 3 21 42 28 -1");
            //116
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static void Main()
    {
        List<string> InputList = GetInputList();

        int[] wkArr = { };
        Action<string> SplitAct = pStr =>
            wkArr = pStr.Split(' ').Select(X => int.Parse(X)).ToArray();

        int N = int.Parse(InputList[0]);

        var FArrList = new List<int[]>();

        foreach (string EachStr in InputList.Skip(1)) {
            SplitAct(EachStr);
            FArrList.Add(wkArr);
        }

        int UB = (1 << N) - 1;

        //相性度合計の最大値[登場した人のBit位置]なDP表
        var PrevDP = new Nullable<int>[UB + 1];
        PrevDP[0] = 0;

        //ペアの作成でループ
        for (int I = 1; I <= N / 2; I++) {
            var CurrDP = new Nullable<int>[UB + 1];
            for (int J = 0; J <= UB; J++) {
                if (PrevDP[J].HasValue == false) continue;

                for (int K = 0; K <= N - 1; K++) {
                    //使用済ならContinue
                    if ((J & DeriveBitPos(K)) > 0)
                        continue;

                    for (int L = K + 1; L <= N - 1; L++) {
                        //使用済ならContinue
                        if ((J & DeriveBitPos(L)) > 0)
                            continue;

                        int NewJ = J;
                        NewJ |= DeriveBitPos(K);
                        NewJ |= DeriveBitPos(L);

                        int NewVal = PrevDP[J].Value + FArrList[K][L];

                        if (CurrDP[NewJ].HasValue && NewVal <= CurrDP[NewJ])
                            continue;

                        CurrDP[NewJ] = NewVal;
                    }

                    //Breakして、最小の人番号からペアを作成するようにする
                    break;
                }
            }
            PrevDP = CurrDP;
        }
        Console.WriteLine(PrevDP[UB]);
    }

    //人番号を引数として対応するビット位置を返す
    static int DeriveBitPos(int pHitoNo)
    {
        return 1 << pHitoNo;
    }
}