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# (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 AtCoder105 {
    class Program {
        static void Main(string[] args) {
            string input = Console.ReadLine();
            int n = Convert.ToInt32(input);
            var divisor = new Divisor();
            int ans = divisor.Count(n, 8);
            Console.WriteLine(ans);
        }
    }
    public class Divisor {
        public int Count(int n) {
            int ans = 0;
            int max = (int)Math.Sqrt(n);
            for(int i = 1; i < max; i += 2) {
                if(n % i == 0) ans++;
            }
            return ans * 2;
        }

        public int Count(int n, int c) {
            //1 以上 n 以下の奇数のうち, 正の約数を ちょうど c 個持つようなものの個数を返す
            int ans = 0;
            for(int i = 1; i <= n; i += 2) {
                if(Count(i) == c) ans++;
            }
            return ans;
        }
    }

}