using Yorukatsu042.Questions;
using Yorukatsu042.Extensions;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace Yorukatsu042.Questions
{
    /// <summary>
    /// ABC074 D
    /// </summary>
    public class QuestionE : AtCoderQuestionBase
    {
        public override IEnumerable<object> Solve(TextReader inputStream)
        {
            var cities = inputStream.ReadInt();
            var map = new long[cities, cities];
            var roads = new long[cities, cities];

            for (int i = 0; i < cities; i++)
            {
                var row = inputStream.ReadLongArray();
                for (int j = 0; j < row.Length; j++)
                {
                    map[i, j] = row[j];
                }
            }

            Array.Copy(map, roads, map.Length);

            const long Inf = 1L << 50;

            for (int k = 0; k < cities; k++)
            {
                for (int i = 0; i < cities; i++)
                {
                    for (int j = 0; j < cities; j++)
                    {
                        if (i == j || j == k || k == i || roads[i, k] == Inf || roads[k, j] == Inf)
                        {
                            continue;
                        }
                        else if (map[i, j] > roads[i, k] + roads[k, j])
                        {
                            yield return -1;
                            yield break;
                        }
                        else if (map[i, j] == roads[i, k] + roads[k, j])
                        {
                            roads[i, j] = Inf;
                        }
                    }
                }
            }

            long totalDistances = 0;
            for (int i = 0; i < cities; i++)
            {
                for (int j = i + 1; j < cities; j++)
                {
                    if (roads[i, j] != Inf)
                    {
                        totalDistances += roads[i, j];
                    }
                }
            }

            yield return totalDistances;
        }
    }
}


namespace Yorukatsu042
{
    class Program
    {
        static void Main(string[] args)
        {
            IAtCoderQuestion question = new QuestionE();    // 問題に合わせて書き換え
            var answers = question.Solve(Console.In);
            foreach (var answer in answers)
            {
                Console.WriteLine(answer);
            }
        }
    }
}

#region Base Classes

namespace Yorukatsu042.Questions
{

    public interface IAtCoderQuestion
    {
        IEnumerable<object> Solve(string input);
        IEnumerable<object> Solve(TextReader inputStream);
    }

    public abstract class AtCoderQuestionBase : IAtCoderQuestion
    {
        public IEnumerable<object> Solve(string input)
        {
            var stream = new MemoryStream(Encoding.Unicode.GetBytes(input));
            var reader = new StreamReader(stream, Encoding.Unicode);

            return Solve(reader);
        }

        public abstract IEnumerable<object> Solve(TextReader inputStream);
    }

}

#endregion

#region Extensions

namespace Yorukatsu042.Extensions
{
    internal static class TextReaderExtensions
    {
        internal static int ReadInt(this TextReader reader) => int.Parse(ReadString(reader));
        internal static long ReadLong(this TextReader reader) => long.Parse(ReadString(reader));
        internal static double ReadDouble(this TextReader reader) => double.Parse(ReadString(reader));
        internal static string ReadString(this TextReader reader) => reader.ReadLine();

        internal static int[] ReadIntArray(this TextReader reader, char separator = ' ') => ReadStringArray(reader, separator).Select(int.Parse).ToArray();
        internal static long[] ReadLongArray(this TextReader reader, char separator = ' ') => ReadStringArray(reader, separator).Select(long.Parse).ToArray();
        internal static double[] ReadDoubleArray(this TextReader reader, char separator = ' ') => ReadStringArray(reader, separator).Select(double.Parse).ToArray();
        internal static string[] ReadStringArray(this TextReader reader, char separator = ' ') => reader.ReadLine().Split(separator);
    }
}

#endregion

Measured memory_bytes: 22232