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())
print(N%1000)
N=int(input())
if N%1000==0:
    print(0)
else:
    print((N//1000+1)*1000-N)