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: Wrong Answer)

object Main extends App{
  val N = io.StdIn.readLine().toInt
  var sftnum = 0
  for(x <- 1 to N){
    var xs = x.toString.toList.map(_.asDigit)
    var three = 0
    var five = 0
    var seven = 0
    for(i <- 0 until xs.length){
      if(xs(i) == 3){
        three += 1
      }else if(xs(i) == 5){
        five += 1
      }else if(xs(i) == 7){
        seven += 1
      }
    }
    if(three == 1 && five == 1 && seven == 1){
      sftnum += 1
    }
  }
  println(sftnum)
}