Arrays are not the same as pointers!

A common mistake people make in C++ is thinking that arrays and pointers are the same thing. They’re not.

char *p = "hello";
char q[] = "hello";

These 2 lines are very different.

The first is a pointer to a string literal. The string literal is in read only memory. Changing p[i] for any index i is undefined.

The second is a char array initialized with ‘h’, ‘e’, ‘l’, ‘l’, ‘o’, ‘\0’. Changing q[i] for any index i in the range 0..5 is fine.

Consequently:

assert(sizeof(p) == sizeof(char*));
assert(sizeof(q) != sizeof(char*));
assert(sizeof(q) == 6);

Not only are pointers and arrays 2 different things completely, but you can also have pointers to arrays. Most people think that a char* is a pointer to an array. It’s not.

char sz[12];

//This is fine, p points to sz's first element's address
char *p1 = sz;

//Compiling error, Can't convert a pointer to 12 elements to a pointer to a char
char *p2 = &sz;

//This is the correct way to create a pointer to an array
char (*x)[12] = &sz;

//Compiling error, can't convert a pointer to 12 elements to a pointer to 10 elements
char (*y)[10] = &sz;

And of course you can also create references to arrays. But the syntax is just as ugly as the syntax for pointers to arrays.

//r is now a reference to sz
char (&r)[12] = sz;