#include <stdio.h>
#include <string.h>

int main(void){
	char val[15];
	scanf("%s",val);
	int count = 3 - (int)strlen(val) % 3;
	if(count == 3){
		count = 0;
	}

	for(int i = 0 ; i < (int)strlen(val);i ++){
		printf("%c",val[i]);
		count++;
		if(count == 3 && i != (int)strlen(val) - 1){
			printf(",");
			count = 0;
		}
	}
}