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 Rust (1.15.1) (judge verdict: Accepted)

fn get_line() -> String {
    let mut line = String::new();
    std::io::stdin().read_line(&mut line).unwrap();
    line.trim().to_string()
}

fn get_divisor_count(num: u64) -> u64 {
    let mut count = 0;
    for i in 1..num + 1 {
        if num % i == 0 { count += 1; }
    }
    count
}

fn main() {
    let num = get_line().parse::<u64>().unwrap();
    let mut result = 0;
    for n in (1..num + 1).filter(|&x| x % 2 != 0) {
        if get_divisor_count(n) == 8 {
            result += 1;
        }
    }
    println!("{}", result);
}