19 (10cc)=16+2+1=10011 (10cc)
31 (10cc)= 32-1 =11111 (2cc); !31=00000
31 | !31=11111
19&31 | 19&!31= 19&(31 | !31)=19=10011
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15 (10cc)=16-1=1111 (2cc)
15|15&19= 1111 |1111 &10011=1111
31&(15 | 15&19)=11111 & 1111=1111
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19^19=10011 ^10011 =00000
23=16+4+2+1=10111 (2cc)
00000^10111=10111
10111 | 1111=11111 (2cc) = 31 (10cc)
ответ 31