Break the PIN.cs

void Main()
{
    Parallel.For(0, 9999999, (pin, loop) =>
    {             
        using(var sha1 = new SHA1Cng())
        using(var sha256 = new SHA256Cng())
        using(var md5 = new MD5Cng())
        {            
            byte[] data = Encoding.ASCII.GetBytes(pin.ToString("D7"));
                    
            if (GetHexResult(data, sha1).Substring(0, 2) == "F1"
            && GetHexResult(data, sha256).Substring(30, 2) == "91"
            && GetHexResult(data, md5).Substring(30, 2) == "5A")
            {
                pin.ToString("D7").Dump();
                
                loop.Stop();
            }
        }
    });
}

// Define other methods and classes here

public static string GetHexResult(byte[] data, HashAlgorithm algorithm)
{
    return algorithm.ComputeHash(data).ToHexString();
}

public static class MyExtensions
{
    // Write custom extension methods here. They will be available to all queries.

    // Source: http://stackoverflow.com/a/14333437
    public static string ToHexString(this byte[] bytes)
    {
        if (bytes == null)
        {
            throw new ArgumentNullException("bytes", "The byte array was null.");
        }
        
        int b;
    
        char[] chars = new char[bytes.Length * 2];
        
        for (int i = 0; i < bytes.Length; i++)
        {
            b = bytes[i] >> 4;
            
            chars[i * 2] = (char)(55 + b + (((b - 10) >> 31) & -7));
            
            b = bytes[i] & 0xF;
            
            chars[i * 2 + 1] = (char)(55 + b + (((b - 10) >> 31) & -7));
        }
        
        return new string(chars);
    }
}