static void Main(string[] args)
{
Rabbit rabbit = new Rabbit();
rabbit.Name = "Cute01";
rabbit.Age = -10;
Console.WriteLine(rabbit.Age);
int x = default; //0
}
static void Main(string[] args)
{
var rabbit = new Rabbit();
rabbit.Name = "Cute01";
// rabbit._bloodType.. INVALID
rabbit.Age = -10;
Console.WriteLine(rabbit.Age);
int x = default; // 0
}