Two identical codes with different outputs

Question

Hello
Why aren't outputs the same?

https://code.sololearn.com/cz0145bf6vSr/?ref=app

https://code.sololearn.com/w6o50b5dOsxR/?ref=app

Answer 1

hosein Zarei

PHP is different than others language.

Here increment happens from right side means ++a first will be increment which will be 2 then $a += 2 now $a is 2 so $a = 2 + 2 = 4

in C#

a += ++a;
a = 1 + 2 = 3

https://code.sololearn.com/w07HrjxKNOct/?ref=app

Answer 2

Languages has their own implementation in which operation will be done first. In a first glance it seems is the same code, but it is not.

Answer 3

The fundamentals for both languages are the same but the implications are different