Pointers and Arrays [ pointers to int vs pointers to char]

Question

Why do pointers behave differently when they are pointing to an integer array and a character array?

For example

int num[] = {1,2,3};
cout << num ;

This prints out the ADDRESS of the first element

char list[] = { '1', '2', '3'};
cout << list ;

This prints out the VALUE of entire elements of array!

Likewise

cout << (num+1) ;

prints out the ADDRESS of the second element. While

cout << (list+1);

prints out the VALUE of entire array beginning from the second element

From my understanding, array name is a pointer to the first element of the array. Without the dereference operator(*), the pointer should return the address of the element. But why is the char pointer returning the value?

The different is that operator<< is an overloaded function, and there is a different overload for char * than for other pointer types — M.M
– M.M, Commented Apr 8, 2017 at 3:21
I didn't realize this problem was specifically for C++. I thought this was related to the Pointers & array concept as a whole. Sorry — Aditya
– Aditya, Commented Apr 8, 2017 at 4:45

Sergey Kalinichenko · Accepted Answer · 2017-04-08 03:26:49Z

5

It is not pointers behaving differently: the behavior is how C++ standard library handles pointer output.

Specifically, operator << has a non-member overload for const char *, which handles null-terminated C strings. This is the overload applied to printing char array. Note that your character array is not null-terminated, so printing it produces undefined behavior. You can fix this by adding zero to the array of characters:

char list[] = { '1', '2', '3', '\0'};

There is also an overload that takes void *, which applies to printing an int pointer.

answered Apr 8, 2017 at 3:26

Sergey Kalinichenko

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1 Comment

Mark Ransom Over a year ago

You can just use 0 instead of'\0.

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