/in/foo.cc: In function 'int main()':
/in/foo.cc:56:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0; i < states.size(); i++)
                  ~~^~~~~~~~~~~~~~~
/in/foo.cc:65:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0; i < states.size(); i++)
                      ~~^~~~~~~~~~~~~~~
/in/foo.cc:66:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int j=0; j < states.size(); j++) next_bp[i][j] = 0;
                          ~~^~~~~~~~~~~~~~~
/in/foo.cc:68:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0; i < states.size(); i++){
                      ~~^~~~~~~~~~~~~~~
/in/foo.cc:71:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for(int j=0; j < states.size(); j++){
                              ~~^~~~~~~~~~~~~~~
/in/foo.cc:85:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0; i < states.size(); i++)
                      ~~^~~~~~~~~~~~~~~
/in/foo.cc:86:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int j=0; j < states.size(); j++) next_bp[i][j] = 0;
                          ~~^~~~~~~~~~~~~~~
/in/foo.cc:89:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int i=0; i < states.size(); i++){
                          ~~^~~~~~~~~~~~~~~
/in/foo.cc:92:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     for(int j=0; j < states.size(); j++){
                                  ~~^~~~~~~~~~~~~~~
/in/foo.cc:95:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                             for(int k=0; k < states.size(); k++){
                                          ~~^~~~~~~~~~~~~~~
/in/foo.cc:91:34: warning: unused variable 'index' [-Wunused-variable]
                     int max = 0, index = -1;
                                  ^~~~~
/in/foo.cc:113:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int i=0; i < states.size(); i++)
                          ~~^~~~~~~~~~~~~~~
/in/foo.cc:114:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for(int j=0; j < states.size(); j++) next_bp[i][j] = 0;
                              ~~^~~~~~~~~~~~~~~
/in/foo.cc:119:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0; i < states.size(); i++){
                  ~~^~~~~~~~~~~~~~~