c and c++ operators help -


Can anyone explain to me why the following results are B = 13? 

  int a, b, c; A = 1 | 2 | 4; B = 8; C = 2; B = A; B & amp; = ~ C; It is using binary manipultaors (assuming that ints are 1 byte, And two supplements for storage, etc.)  
  a = 1 | 2 | 4  means  a = 00000001 or 00000010 or 00000100 , which is 00000111 or 7. 
  b = 8  means  b = 00001000 .  C = 2  means  c = 00000010 . 
  b | = A  device  b = b | A  means  b = 00001000 or 00000111 , which is 00001111 or 15.  ~ c  means  not c , which is 11111101. 
  b & amp; = ~ C  means  b = b & amp; ~ C , which means  B = 00001111 and 11111101 , which is 00001101 or 13.

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