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;
using System.Text;
using System.Threading.Tasks;

namespace C
{
    class Program
    {
        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine());

            int result = 0;

            for(int i = 100; i < N; i++)
            {

                string str = i.ToString();

                if (str.Contains("3")
                    && str.Contains("5")
                    && str.Contains("7")
                    && !str.Contains("0")
                    && !str.Contains("1")
                    && !str.Contains("2")
                    && !str.Contains("4")
                    && !str.Contains("6")
                    && !str.Contains("8")
                    && !str.Contains("9")
                    )
                {
                    result++;
                }

                //for (int j = 0; j < str.Length; j++)
                //{

                //    if (str.Substring(j,1) != "3" && str.Substring(j, 1) != "5" && str.Substring(j, 1) != "7")
                //    {
                //            break;
                //    }

                //    if (j == str.Length - 1)
                //    {
                //        if (str.Contains("3") && str.Contains("5") && str.Contains("7"))
                //        {
                //            result++;
                //        }

                //    }
                //}

            }

            Console.Write(result);
            Console.ReadKey();
        }
    }
}