memory usage of objects

1.Suppose 10 objects are created of the same class. Will all these objects share the same memory?
No the class objects wont share the memory.Each object will have its own memory allocation.But, Static member of a class will be shared by all its objects.

2.In C, we declare an integer as "int i;". In C++ , when we declare "i" as member variable, both "int i" and member variable "i" take the same size?
Yes Both will have same memory size.

Links:
1. http://www.cplusplus.com/doc/tutorial/[^]

2. Use a ANSI compiler and learn debugging.This will help you to clarify this types of doubts

1) Class is a template or blueprint that have functions and member variable. Object is an instance of class. When we create an object than a memory is allocated to that object. This memory is equivalent to the memory of member variable.Exception is if member variable is static than it is shared among all object.functions are loaded once in a memory and shared by every object. sharing of function is done with the help of "this" pointer.
2) Yes. The size of int is always same. The size of int depends on compiler and processor.

Book : Herbert Schildt c++ complete reference
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