Problem:
Score: 200 points

Problem Statement

The number 105 is quite special - it is odd but still it has eight divisors.
Now, your task is this: how many odd numbers with exactly eight positive divisors are there between 1 and N (inclusive)?

Constraints

N is an integer between 1 and 200 (inclusive).

Input

Input is given from Standard Input in the following format:

N

Output

Print the count.

Sample Input 1

105

Sample Output 1

1

Among the numbers between 1 and 105, the only number that is odd and has exactly eight divisors is 105.

Sample Input 2

7

Sample Output 2

0

1 has one divisor. 3, 5 and 7 are all prime and have two divisors. Thus, there is no number that satisfies the condition.

Solution in C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Linq;

namespace atcoder
{
    class Program
    {
        static void Main(string[] args)
        {
            B105(int.Parse(Console.ReadLine()));
        }

        static void B105(int N)
        {
            var count = 0;
            for (var i = 1; i <= N; i += 2)
            {
                if (Counting(i) == 8) count++;
            }
            Console.WriteLine(count);
        }

        static int Counting(int n)
        {
            var count = 0;
            for (var i = 1; i <= n; i ++)
            {
                if (n % i == 0) count++;
            }
            return count;
        }
    }
}