foo.cc:11:26: error: expected unqualified-id before '.' token
 std::vector<int> G[5005];.
                          ^
foo.cc: In function 'bool Find(int)':
foo.cc:17:9: error: 'link' was not declared in this scope
    if (!link[v] || Find(link[v])) return link[v] = u, true;
         ^~~~
foo.cc:17:9: note: suggested alternative: 'Find'
    if (!link[v] || Find(link[v])) return link[v] = u, true;
         ^~~~
         Find
foo.cc: In function 'int main()':
foo.cc:26:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &m, &d);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:28:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lf%lf", x + i, y + i);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:30:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lf%lf%lf", x + i, y + i, v + i);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。