#include<stdio.h>
#include<string.h>
int main() {
	int i = 0;
	int length = 0;
	int rem;
	int count = 0;
	char line[13];
	scanf("%s",line);
	length = strlen(line);
	if(length % 3 == 2) {
		printf("%c%c,", line[i], line[i + 1]);
		rem = 2;
	} else if(length % 3 == 1) {
		printf("%c,", line[i]);
		rem = 1;
	} else if(length % 3 == 0) {
		printf("%c%c%c,", line[i], line[i + 1], line[i + 2]);
		rem = 3;
	}
	for(i = rem;i < length;i++) {
		count++;
		printf("%c",line[i]);
		if(count % 3 == 0 && i != length - 1)
			printf(",");
	}
	return (0);
}