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.
print('N')
x=int(input())
x=1000-x%1000
print(x)
x=int(input())
x=1000-x%1000
if(x==1000):
    x=0
print(x)