static void Main(string[] args)
{
//186p
int n1 = 5;
int n2 = 10;
int sum = n1 + n2;
string txt1 = "123";
string txt2 = "456";
Console.WriteLine(txt1 + txt2);
//187p
Kilogram kg1 = new Kilogram(5);
Kilogram kg2 = new Kilogram(10);
Kilogram kg3 = kg1 + kg2;
Console.WriteLine(kg3);
}
public Kilogram Add(Kilogram target)
{
return(new Kilogram(this.mass + target.mass));
}
