#include <fstream>
#include <iostream>
#include <string>


int main() {

	//std::ifstream inf("Text.txt");	std::cin.rdbuf(inf.rdbuf());

	std::string N;
	std::cin >> N;

	unsigned int c = (N.length() - 1) / 3;

	for (unsigned int i = 1; i <= c; i++) {
		N.insert(N.end() - i * 3 - (i - 1), ',');
	}

	std::cout << N << std::endl;

	return 0;

}