n = int(input())
n = n // 3 * 3
if n < 100:
    ans = 0
    for i in range(1, 10):
        for j in range(0, 10):
            if 10 * i + j <= n and (i + j) % 3 == 0:
                ans += 1
    print(ans)
else:
    s = list(map(int, str(n)))
    d = len(s)
    for i in range(d):
        if s[i] % 3:
            s[i] = s[i] // 3
            for j in range(i + 1, d):
                s[j] = 0
            if s[0] == 0:
                s[1] = 1
            break
        else:
            s[i] //= 3
    ans = 15
    for i in range(d):
        ans += s[i] * 4**(d - 1 - i)
    print(ans)