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run code in 300+ PHP versions simultaneously
<?php $myExistingArray = []; for ($i = 0; $i < 100; $i++) { $myExistingArray[] = ['key1' => '1234', 'key2' => '56', 'count' => 1]; } $myNewArray = []; foreach (array_keys($myExistingArray) as $item) { $myNewArray[$myExistingArray[$item]['key1'] . '_' . $myExistingArray[$item]['key2']] = $myExistingArray[$item]['count']; }
Output for 5.6.0 - 5.6.24, 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
preferences:
49.53 ms | 408 KiB | 5 Q