3v4l.org

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<?php $data = [ 'username' => [ '3805120' => 5, '3805121' => 7, ], 'login' => [ '3805120' => 9, '3805121' => 11, ], ]; $result = array_merge_recursive( array_combine(array_map(function($value) { return 'U'.$value; }, array_keys($data['username'])), $data['username']), array_combine(array_map(function($value) { return 'U'.$value; }, array_keys($data['login'])), $data['login']) ); $result = array_combine( array_map(function($value) { return substr($value, 1); }, array_keys($result)), $result ); var_dump($result);

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