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<?php $a = [ 'firstname' , 'bob' , 'lastname' , 'alex' ]; $new = array_combine( array_intersect_key($a, array_flip(range(0, count($a) - 1, 2))), array_intersect_key($a, array_flip(range(1, count($a) - 1, 2))) ); print_r($new);

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