foo.cc: In function 'int Cnt(std::vector<std::vector<int> >&, std::vector<int>&, std::vector<int>&, int)':
foo.cc:16:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |  for(int i=0;i<tree[root].size();i++)
      |              ~^~~~~~~~~~~~~~~~~~
foo.cc: In function 'long long int Path(std::vector<std::vector<int> >&, std::vector<long long int>&, std::vector<int>&, std::vector<int>&, int)':
foo.cc:33:15: 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<tree[root].size();i++)
      |              ~^~~~~~~~~~~~~~~~~~
foo.cc: In function 'long long int Sum(std::vector<std::vector<int> >&, std::vector<long long int>&, std::vector<int>&, std::vector<int>&, int)':
foo.cc:49:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |  for(int i=0;i<tree[root].size();i++)
      |              ~^~~~~~~~~~~~~~~~~~
foo.cc:57:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |  for(int i=0;i<tree[root].size();i++)
      |              ~^~~~~~~~~~~~~~~~~~
foo.cc:61:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |    for(int j=i+1;j<tree[root].size();j++)
      |                  ~^~~~~~~~~~~~~~~~~~
foo.cc: In function 'int Solve(std::vector<std::vector<int> >&, int, int)':
foo.cc:93:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |   for(int i=0;i<tree[cur].size();i++)
      |               ~^~~~~~~~~~~~~~~~~
foo.cc:76:36: warning: control reaches end of non-void function [-Wreturn-type]
   76 |  vector<bool> vis(tree.size(),false);
      |                                    ^

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