Problem:
Score : 300 points

Problem Statement

You are given an integer N. Among the integers between 1 and N (inclusive), how many Shichi-Go-San numbers (literally "Seven-Five-Three numbers") are there?

Here, a Shichi-Go-San number is a positive integer that satisfies the following condition:

When the number is written in base ten, each of the digits 7, 5 and 3 appears at least once, and the other digits never appear.

Constraints

1 \leq N < 10^9

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the number of the Shichi-Go-San numbers between 1 and N (inclusive).

Sample Input 1

575

Sample Output 1

4

There are four Shichi-Go-San numbers not greater than 575: 357, 375, 537 and 573.

Sample Input 2

3600

Sample Output 2

13

There are 13 Shichi-Go-San numbers not greater than 3600: the above four numbers, 735, 753, 3357, 3375, 3537, 3557, 3573, 3575 and 3577.

Sample Input 3

999999999

Sample Output 3

26484

Solution in Scala (2.11.7) (judge verdict: Runtime Error)

import scala.io.StdIn._

object Main  {
  def main(args: Array[String]): Unit = {
    val n: Int = readLine.toInt
    println(solve(n,0,(false,false,false)))
  }
  def solve(n: Int, x: Int,check:(Boolean, Boolean,Boolean)): Int = {
    val (a,b,c): (Boolean ,Boolean, Boolean) = check
    if(x > n) return 0
    val tmp = if(a && b && c && x <= n) 1 else 0
    val sum1 = solve(n, 10*x + 3, (true,b,c))
    val sum2 = solve(n, 10*x + 5, (a,true,c))
    val sum3 = solve(n, 10*x + 7, (a,b,true))
    sum1+sum2+sum3+tmp
  }
}