foo.cc: In function 'int main()':
foo.cc:54:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |     for (int i = 0; i < graph.size(); i++)
      |                     ~~^~~~~~~~~~~~~~
foo.cc:62:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for (int i = 0; i < graph[0].size(); i++)
      |                     ~~^~~~~~~~~~~~~~~~~
foo.cc:71:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |     for (int i = 1; i < graph.size(); i++)
      |                     ~~^~~~~~~~~~~~~~
foo.cc:73:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   73 |         for (int j = 1; j < graph[i].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~~~

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