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<?php $a = 1; $b = &$a; $c = (++$a)+(++$a)+(++$a); var_dump($c); $x = 1; //$y = &$x; $z = (++$x)+(++$x)+(++$x); var_dump($z);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
int(9) int(9)
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
int(10) int(9)

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151.93 ms | 401 KiB | 179 Q