foo.cc: In function 'void ww(int, int)':
foo.cc:15:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |   for(int i=0;i<v[x].size();i++){
      |               ~^~~~~~~~~~~~
foo.cc: In function 'void dfs(int, int)':
foo.cc:29:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |   for(int i=0;i<v[x].size();i++){
      |               ~^~~~~~~~~~~~

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