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run code in 300+ PHP versions simultaneously
<?php $a = 0x80; var_dump(base_convert($a, 16, 2),$a); $b = ~$a; var_dump(base_convert($b, 16, 2), $b); printf("%b", $b); echo "\n";
Output for 7.4.0 - 7.4.25, 7.4.27 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(9) "100101000" int(128) Deprecated: Invalid characters passed for attempted conversion, these have been ignored in /in/n6q3F on line 5 string(9) "100101001" int(-129) 1111111111111111111111111111111111111111111111111111111101111111
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.26
string(9) "100101000" int(128) string(9) "100101001" int(-129) 1111111111111111111111111111111111111111111111111111111101111111

preferences:
193.23 ms | 405 KiB | 370 Q