nbut [1173] Birdlike Angry Pig 找出某个数使得等于其它所有数的&操作
There'snoendtorevenge.Pigsliketoeatbirds'eggs,sobirdsdecidetorevenge.Forthis,pigsdecidetorevengeaswell.Pigsgiveatasktoabirdlikepig.Theylethesneakintothebirdsgroupsothattheycandestroythebirdsgroup.Ever