foo.cc: In function 'void dfs(int)':
foo.cc:38:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for(int i=0;i<a[u].size();i++)
      |                 ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:47:10: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
   47 |  scanf("%d %d",&n,&k);
      |         ~^     ~~
      |          |     |
      |          int*  long long int*
      |         %lld
foo.cc:47:13: warning: format '%d' expects argument of type 'int*', but argument 3 has type 'long long int*' [-Wformat=]
   47 |  scanf("%d %d",&n,&k);
      |            ~^     ~~
      |             |     |
      |             int*  long long int*
      |            %lld
foo.cc:62:14: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
   62 |     printf("%d",ans);
      |             ~^  ~~~
      |              |  |
      |              |  long long int
      |              int
      |             %lld
foo.cc:47:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   47 |  scanf("%d %d",&n,&k);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   51 |         scanf("%d %d %d",&u,&t,&w);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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