Nine Digit Magic Numbers

NineDigitMagicNumber.cs

using System;

class NineDigitMagicNumbers
{
static void Main()
{
    int sum = int.Parse(Console.ReadLine());
    int diff = int.Parse(Console.ReadLine());
    int abc = 0;
    int def = 0;
    int ghi = 0;
    bool check = false;

    for (int a = 1; a < 8; a++)
    {
        for (int b = 1; b < 8; b++)
        {
            for (int c = 1; c < 8; c++)
            {
                for (int d = 1; d < 8; d++)
                {
                    for (int e = 1; e < 8; e++)
                    {
                        for (int f = 1; f < 8; f++)
                        {
                            for (int g = 1; g < 8; g++)
                            {
                                for (int h = 1; h < 8; h++)
                                {
                                    for (int i = 1; i < 8; i++)
                                    {
                                        abc = a * 100 + b * 10 + c;
                                        def = d * 100 + e * 10 + f;
                                        ghi = g * 100 + h * 10 + i;
                                        if (a+b+c+d+e+f+g+h+i == sum && ghi-def == diff && def-abc == diff && ghi >= def && def >= abc)
                                        {
                                            Console.WriteLine(abc + "" + def + "" + ghi);
                                            check = true;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
    if (check == false)
    {
        Console.WriteLine("No");
    }
}
}