/in/foo.cc: In function 'int main()':
/in/foo.cc:15:6: warning: variable 'p' set but not used [-Wunused-but-set-variable]
  int p;
      ^
/in/foo.cc: In function 'int If_Can(int)':
/in/foo.cc:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < number.size(); i++){
                  ~~^~~~~~~~~~~~~~~
/in/foo.cc:70:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = 0; j < number2.size(); j++){
                   ~~^~~~~~~~~~~~~~~~
/in/foo.cc:71:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int s = 0; s < number3.size(); s++){
                    ~~^~~~~~~~~~~~~~~~