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())
ans=n%1000
print(ans)

n=int(input())
amari=n%1000
if n%1000==0:
    print("0")
else:
    print(1000-amari)
