differnce between pointer and reference





 A pointer can be initialized to any value anytime after it is declared.

 A reference must be initialized when it is declared.

A pointer can be assigned to point to a NULL value.

A pointer can be re-assigned. This property is useful for implementation of data structures like linked list, tree, etc. 

 On the other hand, a reference cannot be re-assigned, and must be assigned at initialization.

Memory Address: 

A pointer has its own memory address and size on the stack whereas 

A reference shares the same memory address (with the original variable) but also takes up some space on the stack.

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