foo.cc: In function 'int main()':
foo.cc:42:55: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |                                         for(int l=0; l<tu[k][j].size(); l++)
      |                                                      ~^~~~~~~~~~~~~~~~

Found 10 testcases.
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