foo.cc: In function 'void dfs(int, int)':
foo.cc:30:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 | for(int i=0;i<g[u].size();i++){
      |             ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:85:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   85 | for(int j=0;j<g[ord[i]].size();j++)
      |             ~^~~~~~~~~~~~~~~~~

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