Generv2

using Newtonsoft.Json;
using System;
using System.Threading;


namespace serialize
{


    class Generator
    {


        public (int, int, int, int) GetMod(int diff)
        {
            int mod1 = 1;// +-
            int mod2 = 1;// +-
            int mod3 = 1;// */
            int mod4 = 1;// */

            if (diff == 0)
            {
                mod1 = 101;// +-
                mod2 = 101;// +-
                mod3 = 11;// */
                mod4 = 11;// */
            }
            if (diff == 1)
            {
                mod1 = 11;
                mod2 = 11;
                mod3 = 10;
                mod4 = 10;
            }
            return (mod1, mod2, mod3, mod4);
        }

        public static char GetSign()
        {

            Random rnd = new Random();
            int tmp = rnd.Next() % 4;
            char result = '.';

            switch (tmp)
            {
                case (0):
                    result = '+';
                    break;
                case (1):
                    result = '-';
                    break;
                case (2):
                    result = '*';
                    break;
                case (3):
                    result = '/';
                    break;
                default:
                    break;
            }
            return result;
        }

        public (int, int) GetPair(int mod1, int mod2)
        {
            Random rnd = new Random();
            int res1, res2;
            res1 = (rnd.Next() % mod1) + 1;
            res2 = (rnd.Next() % mod2) + 1;
            return (res1, res2);
        }



        public (string, char, string, int) Build(char Sign, int diff)
        // first sign second result
        {
            (string, char, string, int) result;
            var MOD = GetMod(diff);
            if (Sign == '+')
            {
                (int, int) Expression = GetPair(MOD.Item1, MOD.Item2);
                result.Item1 = Expression.Item1.ToString();
                result.Item2 = Sign;
                result.Item3 = Expression.Item2.ToString();
                result.Item4 = Expression.Item1 + Expression.Item2;
            }
            else
            if (Sign == '-')
            {
                (int, int) Expression = GetPair(MOD.Item1, MOD.Item2);
                if (Expression.Item1 < Expression.Item2)
                {
                    int a = Expression.Item1;
                    Expression.Item1 = Expression.Item2;
                    Expression.Item2 = a;
                }
                result.Item1 = Expression.Item1.ToString();
                result.Item2 = Sign;
                result.Item3 = Expression.Item2.ToString();
                result.Item4 = Expression.Item1 - Expression.Item2;
            }
            else
            if (Sign == '/')
            {
                (int, int) Expression = GetPair(MOD.Item3, MOD.Item4);
                Expression.Item1 = Expression.Item2 * Expression.Item1;
                result.Item1 = Expression.Item1.ToString();
                result.Item2 = Sign;
                result.Item3 = Expression.Item2.ToString();
                result.Item4 = Expression.Item1 / Expression.Item2;
            }
            else
            {
                (int, int) Expression = GetPair(MOD.Item3, MOD.Item4);
                result.Item1 = Expression.Item1.ToString();
                result.Item2 = Sign;
                result.Item3 = Expression.Item2.ToString();
                result.Item4 = Expression.Item1 * Expression.Item2;
            }

            return result;
        }


        static void Main(string[] args)
        {
            int diff = 0;



            //for (int i = 0; i < 25; ++i)
            {
            Generator abs = new Generator();

                //for (int j = 0; j < 6500000; j++) ;
                var a = abs.Build(GetSign(), diff);
                Thread.Sleep(1);
                var b = abs.Build(GetSign(), diff);




        //      Console.WriteLine(a);
    //          Console.WriteLine(b);




            }
        }

    }
}