using System;
using System.Text;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using static System.Console;
using static System.Math;

namespace AtCorder
{
    class Program
    {
        static void Main(string[] args)
        {
            new Program().Solve(new ConsoleInput(Console.In, ' '));
        }


        public void Solve(ConsoleInput cin)
        {
            var N = cin.ReadInt;
            var map = new int[N, N];
            var B = new int[N, N];

            for (int i = 0; i < N; i++)
            {
                for(int j = 0; j < N; j++)
                {
                    var A = cin.ReadInt;
                    map[i, j] = A;
                    B[i, j] = A;

                }
            }
            var ans = 0L;
            var flag = new bool[N, N];
            for(int k = 1; k <= N; k++)
            {
                for(int i = 1; i <= N; i++)
                {
                    for(int j = 1; j <= N; j++)
                    {
                        if (B[i - 1, j - 1] > B[i - 1, k - 1] + B[k - 1, j - 1])
                        {
                            WriteLine(-1);
                            return;
                        }
                        if(k != i && k != j)
                        {
                            if(B[i - 1, j - 1] == B[i - 1, k - 1] + B[k - 1, j - 1])
                            {
                                flag[i - 1, j - 1] = true;
                                flag[j - 1, i - 1] = true;
                            }
                        }
                    }
                }
            }
            for(int i = 0; i < N; i++)
            {
                for(int j = i + 1; j < N; j++)
                {
                    if (flag[i, j]) continue;
                    ans += map[i, j];
                }
            }
            WriteLine(ans);
        }

        public class ConsoleInput
        {
            private readonly System.IO.TextReader _stream;
            private char _separator = ' ';
            private Queue<string> inputStream;
            public ConsoleInput(System.IO.TextReader stream, char separator = ' ')
            {
                this._separator = separator;
                this._stream = stream;
                inputStream = new Queue<string>();
            }
            public string Read
            {
                get
                {
                    if (inputStream.Count != 0) return inputStream.Dequeue();
                    string[] tmp = _stream.ReadLine().Split(_separator);
                    for (int i = 0; i < tmp.Length; ++i)
                        inputStream.Enqueue(tmp[i]);
                    return inputStream.Dequeue();
                }
            }
            public string ReadLine { get { return _stream.ReadLine(); } }
            public int ReadInt { get { return int.Parse(Read); } }
            public long ReadLong { get { return long.Parse(Read); } }
            public double ReadDouble { get { return double.Parse(Read); } }
            public string[] ReadStrArray(long N) { var ret = new string[N]; for (long i = 0; i < N; ++i) ret[i] = Read; return ret; }
            public int[] ReadIntArray(long N) { var ret = new int[N]; for (long i = 0; i < N; ++i) ret[i] = ReadInt; return ret; }
            public long[] ReadLongArray(long N) { var ret = new long[N]; for (long i = 0; i < N; ++i) ret[i] = ReadLong; return ret; }
        }
    }
}


Measured memory_bytes: 19548