foo.cc: In function 'int main()':
foo.cc:26:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |         for(int i=0;i<e[x].size();i++){
      |                     ~^~~~~~~~~~~~

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