foo.cc: In function 'std::vector<int> solve(std::vector<int>&, std::vector<int>&)':
foo.cc:11:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         while (i < a.size() && j < b.size())
      |                ~~^~~~~~~~~~
foo.cc:11:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         while (i < a.size() && j < b.size())
      |                                ~~^~~~~~~~~~
foo.cc:16:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         while (i < a.size())
      |                ~~^~~~~~~~~~
foo.cc:18:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |         while (j < b.size())
      |                ~~^~~~~~~~~~

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