#include <iostream>
#include <list>
#include <vector>
#include <string>
#include <stdio.h>
#include <stdint.h>
#include <iomanip>
using namespace std;

using uint = unsigned int;
using ll = long long;

#define CIN( LL , A ) LL A; cin >> A 
#define GETLINE( A ) string A; getline( cin , A ) 
#define FOR_ITR( ARRAY , ITR , END ) for( auto ITR = ARRAY .begin() , END = ARRAY .end() ; ITR != END ; ITR ++ ) 

int main()
{

  CIN( string , N );
  const ll size = N.size();
  string answer = "";

  for( ll i = 0 ; i < size ; i++ ){

    answer = N.substr( size - 1 - i , 1 ) + answer;

    if( i % 3 == 2 && i + 1 != size ){

      answer = "," + answer;

    }
    
  }
  
  cout << answer << endl;
  return 0;

}