/in/foo.cc: In function 'void f1(std::vector<std::vector<std::vector<int> > >&, int, int, int)':
/in/foo.cc:17:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (x < A.size() - 1)   f1(A, x + 1, y, z);
       ~~^~~~~~~~~~~~~~
/in/foo.cc:19:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (y < A[0].size() - 1)  f1(A, x, y + 1, z);
       ~~^~~~~~~~~~~~~~~~~
/in/foo.cc:21:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (z < A[0][0].size() - 1) f1(A, x, y, z + 1);
       ~~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'void f0(std::vector<std::vector<std::vector<int> > >&)':
/in/foo.cc:27:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < A[0].size(); i++)//y
                  ~~^~~~~~~~~~~~~
/in/foo.cc:35:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < A[0].size(); i++)//y
                  ~~^~~~~~~~~~~~~
/in/foo.cc:37:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int k = 0; k < A.size(); k++)//x
                   ~~^~~~~~~~~~
/in/foo.cc:43:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int k = 0; k < A.size(); k++)//x
                  ~~^~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < A[0].size(); i++)
                  ~~^~~~~~~~~~~~~
/in/foo.cc:73:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int k = 0; k < A.size(); k++)
                    ~~^~~~~~~~~~