Increment operator's behavior

Question

Why does

int a, b = 10;
b = b++;
printf ("%d", b);

output 10

while

int a, b = 10;
a = b++;
printf ("%d", b);

outputs 11

how does this work? Why doesn't 'b' increment in first case?

other hint: you aren't officially allowed to change b twice in the same instruction. Different compilers might compile it differently. — user253751, Apr 01 '21 at 10:32
See [Why can't we mix increment operators like i++ with other operators?](https://software.codidact.com/posts/278384) — Lundin, Apr 01 '21 at 13:06

score 0 · Accepted Answer · answered Apr 01 '21 at 10:35

b++ performs assignment with not-incremented value while ++b would do assignment with the incremented value. You only need b++; in your code without assignment to increment. As someone also pointed out b = b++; and b = ++b; are not good segments of code and you are at the mercy of the compiler.

Increment operator's behavior

1 Answers1