foo.cc: In function 'void dfs(int)':
foo.cc:9:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |     for(int i=0; i<q[x].size(); i++)
      |                  ~^~~~~~~~~~~~

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Found 10 testcases.
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