# -*- coding: utf-8 -*-

n = int(input())

n = list(str(n))
n.reverse()

zure = -1

for index, item in enumerate(n[:]):
    if(index % 3 == 0):
        n = n[:index+zure+1] + [","] + n[index+1+zure:]
        zure += 1
if n[0] == ",":
    del n[0]

n.reverse()
n = "".join(n)

print(n)