import math


def bf(n):
    d = int(math.log10(n)) + 1
    digits = [int(c) for c in str(n)]

    cnt = 0
    for i in range(12, n+1, 3):
        if i < 100:
            cnt += 1
        elif all([c in '0369' for c in str(i)]):
            cnt += 1
    return cnt


def solve(n):
    d = int(math.log10(n)) + 1
    digits = [int(c) for c in str(n)]

    leading_zero = [0, 0, 30] + [3*4**i for i in range(2, 10)]
    if n < 100:
        cnt = 0
        for i in range(12, n+1, 3):
            cnt += 1
        return (cnt)
    else:
        dp = [[0]*2 for i in range(d)]
        GREATEST = 0
        LESS = 1
        dp[0][GREATEST] = 1 if digits[0] % 3 == 0 else 0
        dp[0][LESS] = max(digits[0]-1, 0)//3
        for i in range(1, d):
            dp[i][GREATEST] = dp[i-1][GREATEST] * \
                (1 if digits[i] % 3 == 0 else 0)
            if digits[i] > 0:
                dp[i][LESS] = dp[i-1][GREATEST] * (max(digits[i]-1, 0)//3 + 1)
            dp[i][LESS] += dp[i-1][LESS] * 4
        return (sum(dp[d-1]) + sum(leading_zero[:d]))


def main():
    n = int(input())
    print(solve(n))


if __name__ == "__main__":
    main()