Package for this problem was not updated by the problem writer or Codeforces administration after we’ve upgraded the judging servers. To adjust the time limit constraint, solution execution time will be multiplied by 2. For example, if your solution works for 400 ms on judging servers, then value 800 ms will be displayed and used to determine the verdict.

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

B. Undoubtedly Lucky Numbers

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputPolycarpus loves lucky numbers. Everybody knows that lucky numbers are positive integers, whose decimal representation (without leading zeroes) contain only the lucky digits *x* and *y*. For example, if *x* = 4, and *y* = 7, then numbers 47, 744, 4 are lucky.

Let's call a positive integer *a* undoubtedly lucky, if there are such digits *x* and *y* (0 ≤ *x*, *y* ≤ 9), that the decimal representation of number *a* (without leading zeroes) contains only digits *x* and *y*.

Polycarpus has integer *n*. He wants to know how many positive integers that do not exceed *n*, are undoubtedly lucky. Help him, count this number.

Input

The first line contains a single integer *n* (1 ≤ *n* ≤ 10^{9}) — Polycarpus's number.

Output

Print a single integer that says, how many positive integers that do not exceed *n* are undoubtedly lucky.

Examples

Input

10

Output

10

Input

123

Output

113

Note

In the first test sample all numbers that do not exceed 10 are undoubtedly lucky.

In the second sample numbers 102, 103, 104, 105, 106, 107, 108, 109, 120, 123 are not undoubtedly lucky.

Codeforces (c) Copyright 2010-2019 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Oct/15/2019 10:40:32 (e1).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|