Function leetcode_for_rust::cd0242_valid_anagram::is_anagram

pub fn is_anagram(s: String, t: String) -> bool

Solutions

Approach 1: HashMap

• Time complexity: O(n)

• Space complexity: O(1)

use std::collections::HashMap;

pub fn is_anagram(s: String, t: String) -> bool {
    if s.len() != t.len() { return false; }

    let mut s_hash = HashMap::new();
    let mut t_hash = HashMap::new();

    for c in s.chars() {
        *s_hash.entry(c).or_insert(0) += 1;
    }

    for c in t.chars() {
        *t_hash.entry(c).or_insert(0) += 1;
    }

    for (key, val) in s_hash.iter() {
        if t_hash.get(key) != Some(val) { return false; }
    }

    true
}

Approach 2: Vec Sort

• Time complexity: O(nlogn)

• Space complexity: O(1)

pub fn is_anagram(s: String, t: String) -> bool {
    if s.len() != t.len() { return false; }

    let mut s_chars: Vec<char> = s.chars().collect();
    let mut t_chars: Vec<char> = t.chars().collect();

    s_chars.sort_by(|a, b| a.cmp(b));
    t_chars.sort_by(|a, b| a.cmp(b));

    s_chars == t_chars
}