def bit_num_sum(num):
    bit_num = bin(num)[2:]
    bit_num_str_list = list(str(bit_num))
    bit_num_int_list = list(map(int, bit_num_str_list))
    return sum(bit_num_int_list)


N = int(input())

# dp[i] iに到達できる最短の移動数、不可能なら'-1'
dp = [-1] * (N + 1)
dp[1] = 1
for i in range(1, N + 1):
    ikisaki = i + bit_num_sum(i)
    if ikisaki <= N and dp[i] != -1:
        dp[ikisaki] = dp[i] + 1
        modori = ikisaki - bit_num_sum(ikisaki)
        if 1 <= modori <= N and (dp[modori] == -1 or dp[modori] >= dp[ikisaki] + 1):
            dp[modori] = dp[ikisaki] + 1

print(dp[N])