/in/foo.cc:8:1: warning: multi-line comment [-Wcomment]
 //          / \\|||   :   |||// \
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:35:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < s.size(); i++)
                  ~~^~~~~~~~~~
/in/foo.cc:40:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < s.size()-1; i++)
                  ~~^~~~~~~~~~~~
/in/foo.cc:47:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (j = 0; j < v.size(); j++)
                ~~^~~~~~~~~~
/in/foo.cc:55:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (j == v.size())
        ~~^~~~~~~~~~~
/in/foo.cc:60:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < v.size(); i++)
                  ~~^~~~~~~~~~
/in/foo.cc:66:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < v.size(); i++)
                  ~~^~~~~~~~~~
/in/foo.cc:74:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < w.size(); i++)
                  ~~^~~~~~~~~~