/in/foo.cc: In function 'int main()':
/in/foo.cc:9:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for(int j=0;j<=s.size();j++)
                  ~^~~~~~~~~~
/in/foo.cc:26:14: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
       else if(s[j]==3)
              ^
/in/foo.cc:19:14: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
       else if(s[j]==2)
              ^