/in/foo.cc: In member function 'int solve::ad(int, int)':
/in/foo.cc:24:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In member function 'int solve::add(int, int, int)':
/in/foo.cc:31:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In member function 'int solve::tarjan(int)':
/in/foo.cc:43:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:47:23: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(f,sizeof(f),0);memset(edge,sizeof(edge),0);memset(query,sizeof(query),0);
                       ^
/in/foo.cc:47:51: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(f,sizeof(f),0);memset(edge,sizeof(edge),0);memset(query,sizeof(query),0);
                                                   ^
/in/foo.cc:47:81: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(f,sizeof(f),0);memset(edge,sizeof(edge),0);memset(query,sizeof(query),0);
                                                                                 ^
/in/foo.cc:48:23: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(h,sizeof(h),0);memset(he,sizeof(he),0);memset(v,sizeof(v),0);
                       ^
/in/foo.cc:48:47: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(h,sizeof(h),0);memset(he,sizeof(he),0);memset(v,sizeof(v),0);
                                               ^
/in/foo.cc:48:69: warning: 'memset' used with constant zero length parameter; this could be due to transposed parameters [-Wmemset-transposed-args]
   memset(h,sizeof(h),0);memset(he,sizeof(he),0);memset(v,sizeof(v),0);
                                                                     ^