Given an array of strings strs, group the anagrams together. You can return the answer in any order.

An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.

Example 1:

Input: strs = [“eat”,“tea”,“tan”,“ate”,“nat”,“bat”] Output: [[“bat”],[“nat”,“tan”],[“ate”,“eat”,“tea”]]

Example 2:

Input: strs = [“”] Output: [[“”]]

Example 3:

Input: strs = [“a”] Output: [[“a”]]

Constraints:

1 <= strs.length <= 104
0 <= strs[i].length <= 100
strs[i] consists of lowercase English letters.

class Solution:
    def groupAnagrams(self, strs: List[str]) -> List[List[str]]:
        dt = defaultdict(list)
        for s in strs:
            dt[frozenset(Counter(s).items())].append(s)

        return list(dt.values())

pub fn group_anagrams(strs: Vec<String>) -> Vec<Vec<String>> {
    let mut h = HashMap::new();

    for s in strs {
        let mut key: Vec<char> = s.chars().collect();
        key.sort();
        h.entry(key).or_insert(vec![]).push(s);
    }

    h.values().cloned().collect()
}