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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{

    static void Main(string[] args)
    {
        int n = int.Parse(Console.ReadLine());
        int c = 0;
        List<long> list = aaaa(0, n);
        
        foreach(long i in list.Where( x=> x<=n))
        {
            Console.WriteLine(i.ToString());
            string a = i.ToString();
            if(a.IndexOf("3") >= 0 && a.IndexOf("5") >= 0 && a.IndexOf("7") >= 0 &&
                a.Replace("3", "").Replace("5", "").Replace("7", "").Length == 0)
            {
                c++;
            }
        }

        Console.WriteLine(c.ToString());

    }

    static List<long> aaaa(long s, long limit)
    {
        if(s >= limit)
        {
            return null;
        }

        List<long> sss = new List<long>();
        long m = s * 10;
        if(m+3 <= limit)
        {
            sss.Add(m + 3);
        }
        if (m + 5 <= limit)
        {
            sss.Add(m + 5);
        }
        if (m + 7 <= limit)
        {
            sss.Add(m + 7);
        }

        List<long> ss = new List<long>();

        foreach (long st in sss)
        {
            List<long> l = aaaa(st, limit);
            if(l == null)
            {
                break;
            }
            ss.AddRange(l);
        }

        sss.AddRange(ss);
        return sss;
    }

}