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run code in 300+ PHP versions simultaneously
<?php $atcode = '11F5796B61690196'; var_export( strtr( str_repeat(substr($atcode, -2), 2), '012345789ABCDEF', '2301675AB89EFCD' ) );
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
'B6B6'
preferences:
74.01 ms | 406 KiB | 5 Q