a few questions about C++

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  1. #1
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    a few questions about C++

    What is the reference ( & ) operator for?
    What does it mean to use the keyword "operator" like so
    Code:
    MyPointer* operator=( &MyPointer );
    I've also read that vectors, are just bigger arrays, in the form of a container?

    If I have more questions, I'll update the thread.
    Last edited by bobbelPoP; 06-29-2008 at 07:52 PM.

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    & is an address-of operator. By default it returns the address of an object (it has nothing to do with references in that usage).

    For operators like +, =, ++, <<, etc, you can overload their meaning when applied to non built-in types. There is an error in your example because the & should go after the class name instead of before it to indicate that it is a reference.

    A vector is not a bigger array. A vector is a dynamic array. It can grow as you add items and it cleans up after itself. This makes it a better choice than regular dynamic arrays in C++ (arrays created with new[] and destroyed with delete[]).

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    whats the difference between a map and a vector then?

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    whats the difference between a map and a vector then?
    A map is an associative container that maps keys to values. A vector is a sequential container that stores objects contiguously.
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    There are many differences, too many to list. First, they are implemented quite differently.

    From a semantic point of view the vector is sort of like a specific kind of map. It maps consecutive integral indexes from 0 - n to the value stored in the vector. A map can have any type as the key (as long as it has certain traits), it doesn't have to be an integer, it doesn't have to be consecutive, etc.

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