How can I declare and define multiple variables in one line using C++?

Question

I always though that if I declare these three variables that they will all have the value 0

int column, row, index = 0;

Bu

Answer 1

As of 2k18, you can use Structured Bindings:

#include <iostream>
#include <tuple>

int main () 
{
    auto [hello, world] = std::make_tuple("Hello ", "world!");
    std::cout << hello << world << std::endl;
    return 0;
}

Demo

Answer 2

If you declare one variable/object per line not only does it solve this problem, but it makes the code clearer and prevents silly mistakes when declaring pointers.

To directly answer your question though, you have to initialize each variable to 0 explicitly. int a = 0, b = 0, c = 0;.

Answer 3

I wouldn't recommend this, but if you're really into it being one line and only writing 0 once, you can also do this:

int row, column, index = row = column = 0;

Answer 4

As @Josh said, the correct answer is:

int column = 0,
    row = 0,
    index = 0;

You'll need to watch out for the same thing with pointers. This:

int* a, b, c;

Is equivalent to:

int *a;
int b;
int c;