3v4l.org

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<?php $input = ['3' => '4', '4' => '5', '1' => '2']; $allowed = ['1', '2', '3']; $flipAllowed = array_flip($allowed); var_export( array_replace( array_intersect_key($flipAllowed, $input), // filtered allowed array_intersect_key($input, $flipAllowed) // filtered input ) );
Output for 7.4.0 - 7.4.33, 8.0.1 - 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
array ( 1 => '2', 3 => '4', )

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