#include<bits/stdc++.h>
using namespace std;

int main()
{
	string num;
	cin>>num;
	int sub = num.length()%3;
	for(auto i=1;i<=num.length();i++){
		cout<<i;
		if((i-sub)%3 == 0 && i!=num.length()){
			cout<<',';
		}
	}
	return 0;
}