/in/foo.cc: In function 'void sort(std::vector<int>&)':
/in/foo.cc:7:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s2.size();i++)
              ~^~~~~~~~~~
/in/foo.cc:9:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<s2.size()-i-1;j++)
               ~^~~~~~~~~~~~~~
/in/foo.cc: In function 'void minChange(std::vector<int>&)':
/in/foo.cc:25:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<s1.size();i++)
               ~^~~~~~~~~~
/in/foo.cc:27:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<s2.size();j++)
               ~^~~~~~~~~~