foo.cc: In function 'int main()':
foo.cc:9:15: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses]
  if(!(b&(b-1))==1)
               ^~
foo.cc:9:5: note: add parentheses around left hand side expression to silence this warning
  if(!(b&(b-1))==1)
     ^~~~~~~~~~
     (         )
foo.cc:7:8: warning: unused variable 'c' [-Wunused-variable]
  int b,c;
        ^

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