#include <iostream>
#include <map>
#include <list>
int main() {
  std::map<char, int> m;
  for (int i = 'A'; i <= 'Z'; i++)
    m.insert(std::pair<char, int>(i, 0));

  std::string s;
  std::cin >> s;

  std::list<char> l;
  std::map<char, int>::iterator p;
  for (std::string::iterator q = s.begin(); q != s.end(); q++) {
    l.push_back(*q);
    p = m.find(*q);
    if (p != m.end())
      p->second++;
  };
  std::list<char>::iterator r = l.begin();
  while (r != l.end()) {
    p = m.find(*r);
    if (p != m.end())
      if (p->second)
        std::cout << p->first << p->second;
    char ch = *r;
    while (*r == ch)
      r++;
    l.remove(ch);
  }
  return 0;
}
/* end */