Solution.rs

impl Solution {
    fn f(s1: String, s2: String) -> String {
        if s1.contains(&s2) {
            return s1;
        }
        if s2.contains(&s1) {
            return s2;
        }
        for i in 0..s1.len() {
            let s = &s1[i..];
            if s2.starts_with(s) {
                let n = s.len();
                return s1 + &s2[n..];
            }
        }
        s1 + s2.as_str()
    }

    pub fn minimum_string(a: String, b: String, c: String) -> String {
        let s = [&a, &b, &c];
        let perm = [
            [0, 1, 2],
            [0, 2, 1],
            [1, 0, 2],
            [1, 2, 0],
            [2, 0, 1],
            [2, 1, 0],
        ];
        let mut ans = String::new();
        for [i, j, k] in perm.iter() {
            let r = Self::f(Self::f(s[*i].clone(), s[*j].clone()), s[*k].clone());
            if ans == "" || r.len() < ans.len() || (r.len() == ans.len() && r < ans) {
                ans = r;
            }
        }
        ans
    }
}