48
100
40
24.5
Area() 0
. , Area () virtual TwoDShape Triangle Rectangle . TwoDShape Area () , , . Area () , , . , , Area () .
. , Main () TwoDShape, Triangle, Rectangle TwoDShape. , . . , . , , . , TwoDShape, Area (). .
, , . , , . , , . TwoDShape , Area () . .
, , . . , , , . , , . , , . Triangle. , Area (). - , , . C# . .
abstract. , . , , . , virtual. virtual abstract .