Declaring arrays statically, on the stack and heap

[r0bHadz]

Homework Statement

Write three functions in C++ : one that declares a large array statistically, one
that declares the same large array on the stack, and one that creates the same
large array from the heap . Call each of the subprograms a large number of times
(at least 100000) and output the time required by each

Relevant Equations

no equations

I'm confused here. I guess my professor mean "statically" in the problem, but anyways, I thought, in C++, that declaring an array statically is the as declaring the array on the stack?

For example, if I have a function:

void staticArr(){
int a[10000];
}

here I am declaring an array statically and it is being declared on the stack.

Am I wrong here?

Thanks

 

[.Scott]

Use the static keyword - either at file scope or within a function.
static int a[10000];

 

[r0bHadz]

Use the static keyword - either at file scope or within a function.
static int a[10000];

that's the only difference between declaring static and declaring on a stack?

edit: finally found the slide that is suppose to teach me this stuff. I guess I over looked it. You can ignore the above question, I'll be back if I have anymore though.

 

[Mark44]

hat's the only difference between declaring static and declaring on a stack?

All three signify different sections of memory, and are used in different ways.
Static memory is allocated before the program starts to run, and is initialized to zero or whatever the equivalent of zero is for the type of the variable.
Heap memory (AKA free store) is allocated at run time by a call to malloc() or similar in C, or by the new or new[] operators in C++. Stack memory is allocated for local variables and function or method parameters.