foo.cc: In function 'int main()':
foo.cc:81:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<point>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |     for(i=0;i<path.size();i++)
      |             ~^~~~~~~~~~~~
foo.cc:78:8: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   78 |     dfs(pa,x,y,0);
      |     ~~~^~~~~~~~~~
foo.cc:78:8: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]

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