#include <iostream>
#include <sstream>
using namespace std;

string compress(const string &str)
  {
   ostringstream ss;
   for(int ch=0,prv=str[0],count=1,i=1;prv;++i,prv=ch)
     {
      if((ch=str[i])==prv) ++count;
      else if(count==1) ss<<(char)prv;
      else
        {
         ss<<count<<(char)prv;
         count=1;
        }
     }
   return ss.str();
  }
  
int main(void)
  {
   cout<<compress("abcccdefff ffbbcdegg")<<endl;
   cout<<compress("bbba")<<endl;
   return 0;
  }