/* -*- coding: utf-8 -*-
 *
 * 784.cc:  No.784 「,(カンマ)」 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

/* global variables */

char s[16];

/* subroutines */

/* main */

int main() {
  scanf("%s", s);
  int n = strlen(s);

  for (int i = 0; i < n; i++) {
    if (i > 0 && (n - i) % 3 == 0) putchar(',');
    putchar(s[i]);
  }
  putchar('\n');
  return 0;
}