/in/foo.cc: In function 'int main()':
/in/foo.cc:31:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<start.size()-1;++j)
               ~^~~~~~~~~~~~~~~
/in/foo.cc:32:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int t=j+1;t<start.size();++t)
                  ~^~~~~~~~~~~~~
/in/foo.cc:49:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j=0;j<start.size();++j)
                ~^~~~~~~~~~~~~
/in/foo.cc:53:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      r=start[(j+1>start.size()-1?0:j+1)]-'0',
               ~~~^~~~~~~~~~~~~~~
/in/foo.cc:68:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<start.size();++j)
               ~^~~~~~~~~~~~~
/in/foo.cc:71:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     r=start[(j+1>start.size()-1?0:j+1)]-'0';
              ~~~^~~~~~~~~~~~~~~