/in/foo.cc: In function 'int add(int, int, int)':
/in/foo.cc:30:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int dfs(int)':
/in/foo.cc:42:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^