Sorty Numbers

Any non-negative integer (including $0$) is sorty if its digits are in a strictly increasing order, from most significant to least significant. In other words, for any digit, any other digit which has lower significance than it must have strictly greater value.

For example, $167$ is sorty, since $1 < 6$ and $6 < 7$.

$429$ is not sorty, since $4 > 2$.

$444$ is also not sorty, since the digits must be strictly ascending, meaning they cannot be the same.

Given some integer $n$, output the number of sorty numbers in the range $[0, n]$.

Input

A single integer is given, $n$.

Output

Output a single integer, which is the number of sorty numbers less than or equal to $n$.

Constraints

• $0 < n \le 10^9$

Example 1

12

11

Explanation

The first $11$ sorty numbers are: $0, 1, 2, 3, 4, 5, 6, 7, 8, 9$ and $12$.

Example 2

244

80

Example 3

214

74