/in/foo.cc: In function 'void dfs(std::vector<std::vector<int> >&, int, int, int, int, std::vector<int>&)':
/in/foo.cc:8:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (maxlen < temp.size())
        ~~~~~~~^~~~~~~~~~~~~
/in/foo.cc:15:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(x+1<graph.size())
     ~~~^~~~~~~~~~~~~
/in/foo.cc:17:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(y + 1 < graph[0].size())
     ~~~~~~^~~~~~~~~~~~~~~~~