rustgym 0.2.0

rustgym solutions
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

struct Solution;
use rustgym_util::*;

impl Solution {
    fn swap_pairs(head: ListLink) -> ListLink {
        if let Some(mut first) = head {
            if let Some(mut second) = first.next.take() {
                let rest = second.next.take();
                first.next = Self::swap_pairs(rest);
                second.next = Some(first);
                Some(second)
            } else {
                Some(first)
            }
        } else {
            None
        }
    }
}

#[test]
fn test() {
    let head = list!(1, 2, 3, 4);
    let res = list!(2, 1, 4, 3);
    assert_eq!(Solution::swap_pairs(head), res);
}