n = int(input())

if n < 10:
    print(0)
elif n < 100:
    print(n // 3 - 3)
else:
    ans = 30
    s = str(n)
    d = len(s)
    for i in range(3, d):
        ans += 3 * pow(4, i - 1)
    for i in range(d):
        q, r = divmod(int(s[i]), 3)
        if r != 0:
            ans += q * pow(q + 1, d - 1)
        else:
            ans += (q - 1) * pow(q, d - 1)
            if i == 0:
                ans += 1
    print(ans)