abstruct method c#
abstract class Shape
{
public abstract int GetArea();
}
class Square : Shape
{
int side;
public Square(int n) => side = n;
// GetArea method is required to avoid a compile-time error.
public override int GetArea() => side * side;
static void Main()
{
var sq = new Square(12);
Console.WriteLine($"Area of the square = {sq.GetArea()}");
}
}
// Output: Area of the square = 144