#include<iostream>
#include<string>
using namespace std;

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