I do not get this --- int x = 0; int y = 2; int z = (++x, ++y);

Question

int x = 0; 
int y = 2; 
int z = (++x, ++y);

I get that z is 3 because the value is taken from ++y, but why is ++y being chosen?

http://msdn.microsoft.com/en-us/library/zs06xbxh(v=vs.110).ASPX — Joachim Isaksson, Dec 01 '13 at 07:11

score 3 · Answer 1 · answered Dec 01 '13 at 07:10

It's called comma operator. It evaluates ++x(now x is 1), then evaluates ++y(now y is 3) and assign value of y toz``

The ``comma operator groups left-to-right. § 5.18

A pair of expressions separated by a comma is evaluated left-to-right and the value of the left expression is discarded.

score 2 · Answer 2 · answered Dec 01 '13 at 07:10

2

Because (++x,++y) evaluates ++x first, then ++y and whatever was evaluated last is returned and assigned to z.

answered Dec 01 '13 at 07:10

Aniket Inge

score 0 · Answer 3 · answered Dec 01 '13 at 07:12

0

This uses comma operator. The equivalent is:

int x = 0; 
int y = 2; 
++x; // or x = x + 1;
++y; // or y = y + 1;
int z = y;

answered Dec 01 '13 at 07:12

klm123

3 Answers3