/in/foo.cc: In function 'int dfs1(int, int)':
/in/foo.cc:35:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int Query(int, int, int, int)':
/in/foo.cc:162:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^