If that code snippet is represenative of the class you sent me via PM, the problem is that Area is uninitialized.
Shape ShapeTwo; invoke's Shape's default constructor. Shape's default constructor in turn invokes an explicit 4 argument constructor which sets x and y, but does not calculate Area. Therefore, when you try and output Area, Area is an uninitialized variable.
Posting rules here are that you need to post enough of your code to demonstrate the problem. The tiny snippets you posted are not sufficient for anybody not seeing your actual code to ascertain the problem.
The only place I see you calculating Area is inside InputData and then only if name == "Square". Any other logic path, and Area is going to be uninitialized.
There is a calculation inside ComputeArea, but I don't see you call that function.
You also have some logic problems in main.
If option 1 is entered you call inputData, and then call main recursively. You should never call main. Calling main recursively is going to push a new instance of sd and ShapeTwoDD onto the stack. Now, if you select option 2, ShapeTwoDD is uninitialized except for what is set by its default constructor.