NEED HELP

[tanvir 095438]

What is the difference between structure and union?


Mahmudul hasan shovon(095411)
CEE, Islamic University of technology

 

[Bill Reid]

What is the difference between structure and union?

Mahmudul hasan shovon(095411)
CEE, Islamic University of technology

Honest to God truth, I barely know that one my own
self...when you find out, could you post the answer?
TIA.

 

[Ram Prasad]

What is the difference between structure and union?

Mahmudul hasan shovon(095411)
CEE, Islamic University of technology

Is that the university homework ?
Why dont you google that for yourself ?

Thanks
Ram



PS:
Note to Spammers: Go ahead , send me spam
(e-mail address removed)
http://pragatee.com

 

[kathir cpp]

Here is the simple example:

All the members in Union will share the same memory location.
We have a same set of members for MyStruct and MyUnion. Compiler will
allocate 16 bytes for the given structure and allocate just 4 bytes
for the union.

struct MyStruct
{
long lValue;
char ch;
char buf[4];
float f;
};

union MyUnion
{
long lValue;
char ch;
char buf[4];
float f;
};

int _tmain(int argc, _TCHAR* argv[])
{
int sz1 = sizeof(MyStruct); // will be 16 bytes
int sz2 = sizeof(MyUnion); // will be 4 bytes
}

An example in VC++ would be VARIANT class.

To view more details on sizeof, visit at http://www.kathircpp.com

 

[Nick Keighley]

Here is the simple example:

All the members in Union will share the same memory location.
We have a same set of members for MyStruct and MyUnion. Compiler will
allocate 16 bytes for the given structure and allocate just 4 bytes
for the union.

struct MyStruct
{
    long lValue;
    char ch;
    char buf[4];
    float f;

};

union MyUnion
{
    long lValue;
    char ch;
    char buf[4];
    float f;

};

int _tmain(int argc, _TCHAR* argv[])
{
    int sz1 = sizeof(MyStruct); // will be 16 bytes
    int sz2 = sizeof(MyUnion); // will be 4 bytes

}

the actual sizes would be dependent on the implementaion, but you have
the right general idea.