/in/foo.cc: In function 'int main()':
/in/foo.cc:48:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1; i < p.size(); i++) {
                    ~~^~~~~~~~~~
/in/foo.cc:51:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while(L.size() > k) {
           ~~~~~~~~~^~~