# coding utf-8

num = str(input())

"""
num = reversed(num)
i = 0
for n in num:
    i += 1
    ans.append(n)
"""
# len = 3k+0 -> 333,333 あと3
# len = 3k+1 -> 3,333,333 あと1
# len = 3k+2 -> 33,333,333 あと2

i = int(len(num) % 3)
if i == 0:
    i = 3
    
for n in num[:(len(num)-1)]:
    print(n,end="")
    i -= 1
    if i == 0:
        print(",",end="")
        i = 3
print(n[-1])