3v4l.org

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<?php $array = [ 'visitPoints'=>[ 20=>[2,5,6,8,10,11], 35=>[2,5,6], 57=>[1] ], 'islands'=>[ 20=>[5,10,11], 35=>[5,6] ], 'animals'=>[ 20=>[5,11], 35=>[] ] ]; $result = [ 20=>[5,11], 35=>[], 57=>[] ]; print_r($result);

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