foo.cc: In function 'void dfs(int)':
foo.cc:25:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |  for(int i=0; i<g[u].size(); i++)
      |               ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:33:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |  scanf("%lld %lld",&n,&k);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:37:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |   scanf("%d %d %d",&u,&v,&x);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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