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<?php $a = [7, 5, 6, 9]; $b = [1, 3, 2, 4]; $c = array_combine($a,$b); $r = []; array_walk($c, function($k,$v) use (&$r){$r[] = "{$v}-{$k}";}); print_r($r);

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16.98 ms | 406 KiB | 5 Q