Thread: is a string in C = pointer = array?

Basically yeah. Though there is no s[null]...

Lets say you have this code:

Code:

char* s = "abc";

A string will be stored in memory. You will have 4 memory locations with values 'a','b','c','\0'. All strings in C are null terminated, where '\0' is the null character (which is the same with zero). Now, the pointer s points at the first element. So it points at 'a'. As you know you can get 'a' by doing

Code:

*s;

Now lets say you want 'b'. An easy way to get it is use indexes and do

Code:

s[1];

if you know about pointer arithmetic that would be the same by doing

Code:

*(s+1);

and in general

Code:

s[i] == *(s+i)

So what indexes do are give you the character that is shown X amount of elements after where the pointer points, where X is the index (like s[X]).

Note that a pointer can change value which makes it different than a C-array. In the above example you could do

Code:

s = s + 2;

Now, s points at 'c'. If you do

Code:

s[1];

you will get the next character from where s points at. Which is now '\0'.