How To Initialize A Char Array

[Chathu]

Is it a must to specify the size of an array when u initialize it. If so Why it is important give the size?

char whatever[];//method 1
char whatever[]="whatever";//method 2
char whatever[size];//method 3
char whatever[size]="whatever";//method 4

what is the best and correct way to initialize an array from the above??

[coder777]

Is it a must to specify the size of an array when u initialize it.

It is a must (in C++) to specify the size of an array. You may or may not initialize it.

Why it is important give the size?

Because an array without a size don't make sense.

what is the best and correct way to initialize an array from the above??

It depends on the requirements. This char whatever[]="whatever";//method 2 is a good way because the compiler determines the size.

[Chathu]

But some books says that it is not a good programming practice to let the compiler determine the size of an array. for example if i want to keep names in a char array it is a waste of memory to initialize it's size to a constant. because sizes of names can be different.

so in this case if i didnt give the size of the char array is it taking it's default size? What is the default value

[georgewashere]

Chathu, you could always determine the size of the array at runtime?

int size;
cout << "How big of an array?";
cin >> size;
char ch[size];

also take a look at http://www.cplusplus.com/doc/tutorial/dynamic/ if you are concerned about wasting memory.

[Chathu]

Whoa...Thanks This Is Exactly What I Wanted...

[andywestken]

Warning!!

C++ only allows arrays to be defined with a constant size.

georgewhere's example is valid C99, not C++. Unfortunataly some compilers blur the edges between the two languages.

If compiled with a strictly ANSI C++ compiler, the code snippet will fail to compile.