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 Ruby (2.3.3) (judge verdict: Wrong Answer)

require 'set'
n = gets.chomp.to_i

def divisors_count n

  divisors = []

  (n**0.5).to_i.times do |i|
    if i.even?
      next
    end

    if (n % i).zero?
      divisors.push i
      divisors.push n.div(i)
    end
  end

  divisors.to_set.size
end


count = 0

n.times do |i|
  if divisors_count(i + 1) == 8
    count += 1
  end
end

puts count