/in/foo.cc: In function 'int main()':
/in/foo.cc:47:11: warning: 'daymax' may be used uninitialized in this function [-Wmaybe-uninitialized]
    day=day-daymax;
        ~~~^~~~~~~
/in/foo.cc:27:7: note: 'daymax' was declared here
   int daymax;
       ^~~~~~