Säähavainnot

use std::io;

fn main() {
    let (k, mut list) = get_k_and_list();

    let result = match k {
        2 => solve2(&mut list),
        3 => solve3(&list),
        4 => todo!(),
        5 => todo!(),
        _ => unreachable!(),
    };
    dbg!(&list);
    print_results(&result);
}

fn get_k_and_list() -> (usize, Vec<i32>) {
    let mut input = String::new();
    io::stdin().read_line(&mut input).unwrap();
    let mut nums = input
        .split_whitespace()
        .map(|x| x.parse::<usize>().unwrap());
    let _n = nums.next().unwrap();
    let k = nums.next().unwrap();

    let mut input = String::new();
    io::stdin().read_line(&mut input).unwrap();
    let list = input
        .split_whitespace()
        .map(|x| x.parse().unwrap())
        .collect();

    (k, list)
}

fn solve2(list: &mut Vec<i32>) -> Option<Vec<usize>> {
    Some(sort2(list))
}

fn sort2(list: &mut Vec<i32>) -> Vec<usize> {
    let n = list.len();
    let mut result = Vec::new();
    for m in (2..=n).rev() {
        for i in 0..m - 1 {
            if list[i] > list[i + 1] {
                list.swap(i, i + 1);
                result.push(i);
            }
        }
    }
    result
}

fn solve3(list: &Vec<i32>) -> Option<Vec<usize>> {
    let mut part1: Vec<i32> = list.iter().cloned().step_by(2).collect();
    let mut part2: Vec<i32> = list.iter().cloned().skip(1).step_by(2).collect();
    if part1.iter().any(|x| x % 2 != 1) || part2.iter().any(|x| x % 2 != 0) {
        return None;
    }
    let mut seq1 = sort2(&mut part1);
    let mut seq2 = sort2(&mut part2);
    seq1.iter_mut().for_each(|x| *x = 2 * *x);
    seq2.iter_mut().for_each(|x| *x = 2 * *x + 1);
    seq1.append(&mut seq2);

    Some(seq1)
}

fn print_results(result: &Option<Vec<usize>>) {
    match result {
        None => {
            println!("NO")
        }
        Some(ops) => {
            println!("YES");
            println!("{}", ops.len());
            println!(
                "{}",
                ops.iter()
                    .map(|x| (x + 1).to_string())
                    .collect::<Vec<_>>()
                    .join(" ")
            );
        }
    }
}

Test 1

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 2

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 4

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 5

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 6

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 7

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...

Test 8

Verdict: RUNTIME ERROR

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', input/code.rs:24:...