foo.cc: In function 'int main()':
foo.cc:12:23: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses]
  }else if(c=!(b&(b-1))==1)
                       ^~
foo.cc:12:13: note: add parentheses around left hand side expression to silence this warning
  }else if(c=!(b&(b-1))==1)
             ^~~~~~~~~~
             (         )
foo.cc:12:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  }else if(c=!(b&(b-1))==1)
           ~^~~~~~~~~~~~~~

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