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run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr = array( 'operator_id_1' => 'operator_bp_id_100', 'operator_id_2' => 'operator_bp_id_200', 'operator_id_3' => 'operator_bp_id_300', 'operator_id_4' => 'operator_bp_id_400' ); $keys = array_keys($arr); if (($key = array_search("operator_id_2", $keys) - 1) < 0) { $key = count($keys) - 1; } print $keys[$key];
based on TY0K1
Output for 5.6.0 - 5.6.30, hhvm-3.15.4, 7.0.0 - 7.3.0beta1
operator_id_1