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run code in 300+ PHP versions simultaneously
<?php var_dump( mktime(PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX), date('Y-m-d H:i:s', mktime(PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX, PHP_INT_MAX)) );

preferences:
26.24 ms | 406 KiB | 5 Q