We will buy a product for N yen (the currency of Japan) at a shop.  If we use only 1000-yen bills to pay the price, how much change will we receive?  Assume we use the minimum number of bills required.
N = int(input())
while N >= 1000:
  N -= 1000
print(N)
N = int(input())
while N > 0:
  N -= 1000
print(-N)