/in/foo.cc: In function 'void Output(std::vector<int>&)':
/in/foo.cc:20:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < t1.size(); i++)
                  ~~^~~~~~~~~~~
/in/foo.cc: In function 'void Count(char*, int&, char*, int&)':
/in/foo.cc:91:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < t1.size(); i++)
                  ~~^~~~~~~~~~~
/in/foo.cc:93:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = 0; j < t2.size(); j++)
                   ~~^~~~~~~~~~~
/in/foo.cc:86:6: warning: unused variable 't' [-Wunused-variable]
  int t = 0;
      ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:123:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i < s.length())
        ~~^~~~~~~~~~~~
/in/foo.cc:128:49: warning: NULL used in arithmetic [-Wpointer-arith]
    while (s[i] >= '0' && s[i] <= '9' && b[0] == NULL)
                                                 ^~~~