Problem:
Score : 100 points

Problem Statement

Takahashi, who is A years old, is riding a Ferris wheel.

It costs B yen (B is an even number) to ride the Ferris wheel if you are 13 years old or older, but children between 6 and 12 years old (inclusive) can ride it for half the cost, and children who are 5 years old or younger are free of charge. (Yen is the currency of Japan.)

Find the cost of the Ferris wheel for Takahashi.

Constraints

0 ≤ A ≤ 100

2 ≤ B ≤ 1000

B is an even number.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the cost of the Ferris wheel for Takahashi.

Sample Input 1

30 100

Sample Output 1

100

Takahashi is 30 years old now, and the cost of the Ferris wheel is 100 yen.

Sample Input 2

12 100

Sample Output 2

50

Takahashi is 12 years old, and the cost of the Ferris wheel is the half of 100 yen, that is, 50 yen.

Sample Input 3

0 100

Sample Output 3

0

Takahashi is 0 years old, and he can ride the Ferris wheel for free.

Solution in Rust (1.15.1) (judge verdict: Accepted)


// copy from https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        let mut next = || { iter.next().unwrap() };
        input_inner!{next, $($r)*}
    };
    ($($r:tt)*) => {
        let stdin = std::io::stdin();
        let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock()));
        let mut next = move || -> String{
            bytes
                .by_ref()
                .map(|r|r.unwrap() as char)
                .skip_while(|c|c.is_whitespace())
                .take_while(|c|!c.is_whitespace())
                .collect()
        };
        input_inner!{next, $($r)*}
    };
}

macro_rules! input_inner {
    ($next:expr) => {};
    ($next:expr, ) => {};

    ($next:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };
}

macro_rules! read_value {
    ($next:expr, ( $($t:tt),* )) => {
        ( $(read_value!($next, $t)),* )
    };

    ($next:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
    };

    ($next:expr, chars) => {
        read_value!($next, String).chars().collect::<Vec<char>>()
    };

    ($next:expr, usize1) => {
        read_value!($next, usize) - 1
    };

    ($next:expr, $t:ty) => {
        $next().parse::<$t>().expect("Parse error")
    };
}

fn main() {
    input! {
        a: usize,
        b: usize,
    }
    println!("{}", solve(a, b));
}

fn solve(a: usize, b: usize) -> usize {
    if a >= 13 {
        b
    } else if a >= 6 {
        b / 2
    } else {
        0
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test() {
        let tests: Vec<((usize, usize), usize)> = vec![
            ((30, 100), 100),
            ((12, 100), 50),
            ((0, 100), 0),
        ];
        for t in tests.iter() {
            let ((a, b), expected) = t;
            let actual = solve(*a, *b);
            assert_eq!(actual, *expected);
        }
    }
}