#include <bits/stdc++.h>
#define rep(i, ss, ee) for (int i = ss; i < ee; ++i)
using namespace std;

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

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
  getchar();
}