foo.cc: In function 'bool check(int, ma)':
foo.cc:33:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |     for(int i=0;i<y.boom.size();i++)
      |                 ~^~~~~~~~~~~~~~

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