l = [15, 24, 42, 51, 18, 27, 45, 54, 72, 81, 12, 21, 84, 75, 57, 48, 87, 78]
n = int(input())
s = [0]
st = set()
while s:
    p = s.pop()
    if p in st or p > n:
        continue
    l.append(p)
    st.add(p)
    s.append(p * 10)
    s.append(p * 10 + 3)
    s.append(p * 10 + 6)
    s.append(p * 10 + 9)
ans = 0
for x in l:
    if 10 <= x <= n:
        ans += 1
print(ans)