Differance in arrays

[Shane]

hi,

I have a question in C++ arrays.
Is it equal to define int myArray[256] and int *myArray = new int[256]; ?

Regards,

Shane

[Neo]

There two ways to define arrays in C++. Static and dynamic definitions.

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int myArray[256];                 // Static definition
int *myArray = new int[256]; // Dynamic definition

When accessing the arrays there is no difference. However Static arrays are created at function load-time and the size of the array is fixed.

Dynamic arrays are created at run-time and the size can be adjusted as required anywhere in the code.

There is one important thing about dynamic arrays. Whenever you don't need the dynamic array anymore, it is required to remove it from memory by using 'delete' statement to avoid memory leaks.

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int size = 256;
int *myArray = NULL;       // new pointer declared
myArray = new int [size]; // memory dynamically allocated
 
/* .......
Your code here
........*/
 
delete [] myArray;           // memory freed up
myArray = NULL;             // pointer changed to NULL

To avoid unnecessary problems, try to use statically defined arrays as much as possible. Only use dynamic array when it is really required.

Does that make sense?

[Shane]

Thanks. Got it.