#include <iostream>

int main(void){
  std::string a;
  std::cin >> a;
  const char* ca = a.c_str();
  int len=a.length();
  for(int i=0;i<a.length();i++){
    std::cout << ca[i];
    if(((a.length()-i-1)%3==0)&&i!=a.length()-1) std::cout <<",";
  }
}