What's the difference between int *p = &a and q = &a

Question

Learner question. I can declare and initialize a pointer in two different way

int a = 10;
int *p = &a;

also

int a = 10;
int *q;
q = &a;

I want to know what is the difference between two and how does it work in the memory?

Answer 1

Those two are the same :

int *p; // declaration
p = &a; // assignment

and in the other you are combining the two steps together into one:

int *p=&a; // declaration and assignment

And if you have some compiler optimizations ON, the compiler might combine the two steps.