#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<vector>
#include<string>
#include<sstream>
#include<cmath>
#include<numeric>
#include<map>
#include<stack>
#include<queue>
using namespace std;


int main(void) {
  string s; cin >> s;
  int p = s.size()%3;
  for(int i=0; i<s.size(); i++) {
    cout << s[i];
    if((i+1)%3 == p && i != s.size()-1) cout << ",";
  }
  cout << endl;
  return 0;
}






// EOF