/in/foo.cc: In function 'int MAX(int, int, int, int)':
/in/foo.cc:9:7: warning: variable 'res' set but not used [-Wunused-but-set-variable]
   int res=0;
       ^~~
/in/foo.cc:11:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^