Question

What is the difference between int and char arrays below:

int main()
{
    int numbers[] = {2,1,3};
    char letter[] = {'a','b','\0'};
    cout<< numbers<<endl;
    cout<< letter<<endl;
}

Output:

0x22ff12 // an address
ab

Why isn’t the 213 displayed ?
I know the name of an array will point to the address of its first element, but why
does a char array display different behavior?

Answer 1

There is no operator<< overload that takes arrays, exactly, so the arguments you pass (eg numbers and letter) undergo array-to-pointer conversion, to void* and char* respectively.

There is an overload of operator<<() that takes a const void*, and another that takes a const char*. When you call:

cout<< numbers<<endl;

the const void* version is matched, but when you call:

cout<< letter<<endl;

the const char* version is matched.

In the const void* version, the pointer is displayed, while with the const char* version, the string is displayed up to the null terminator.