foo.cc: In function 'bool dfs(int, int)':
foo.cc:17:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |    for (int i=0;i<e[u].size();i++){
      |                 ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:30:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |         scanf("%lf%lf",&p[i].x,&p[i].y);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:32:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |         scanf("%lf%lf%lf",&q[i].x,&q[i].y,&q[i].v);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务