LeetCode 953. Verifying an Alien Dictionary

Problem Statement

use std::collections::HashMap;

impl Solution {
    fn compare(w1: &String, w2: &String, map: &HashMap<char, usize>) -> bool {
        let size = std::cmp::min(w1.len(), w2.len());
        for i in 0..size {
            let (i1, i2) = (
                *map.get(&w1.chars().nth(i).unwrap()).unwrap(),
                *map.get(&w2.chars().nth(i).unwrap()).unwrap());
            if i1 > i2 {
                return false;
            } else if i1 == i2 {
                continue;
            } else {
                return true;
            }
        }

        if w1.len() > w2.len() {
            return false;
        }

        return true;
    }
    pub fn is_alien_sorted(words: Vec<String>, order: String) -> bool {
        let mut map = HashMap::new();
        for i in 0..order.len() {
            map.insert(order.chars().nth(i).unwrap(), i);
        }
        for i in 0..words.len() - 1 {
            if Self::compare(&words[i], &words[i + 1], &map) {
                continue;
            }
            return false;
        }
        return true;
    }
}