foo.cc: In function 'bool isRepeat(std::vector<Node>&, int, int)':
foo.cc:31:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Node>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |         for(int k=0;k<Path.size(); k++)
      |                     ~^~~~~~~~~~~~
foo.cc: In function 'int bfs(std::vector<std::vector<char> >&, int, int)':
foo.cc:29:1: warning: control reaches end of non-void function [-Wreturn-type]
   29 | }
      | ^

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