N = int(input())

ok = 1 << 30; ng = -1

while ok - ng > 1:
    mid = (ok + ng) >> 1
    if mid * 500 >= N:
        ok = mid
    else:
        ng = mid


for i in range(max(0, ok - 3), ok + 3):
    if N - i * 500 < 100:
        print(i)
        exit()