/in/foo.cc: In member function 'bool Date::runnian(int)':
/in/foo.cc:18:24: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
         if (y % 4 == 0 && y % 100 != 0 || y % 400 == 0)
             ~~~~~~~~~~~^~~~~~~~~~~~~~~
/in/foo.cc: In member function 'int Date::monthday(int, int)':
/in/foo.cc:36:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^