foo.cc: In function 'int main()':
foo.cc:31:31: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   31 |             if((i >> stage)&1 == 0) continue;
      |                             ~~^~~~
foo.cc:34:35: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   34 |                     if((i >> u)&1 == 0) continue;
      |                                 ~~^~~~

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