Group Anagrams

Description

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.

Solution(javascript)

/**
 * @param {string[]} strs
 * @return {string[][]}
 */
var groupAnagrams = function(strs) {
    // does not work on all cases
    // let anagrams = {};
    // for (let i = 0; i < strs.length; i++){
    //     let sorted = strs[i].split("").sort().join("");
    //     if(anagrams[sorted]) {
    //         anagrams[sorted] += "," + [strs[i]] 
    //     } else {
    //         anagrams[sorted] = strs[i]
    //     }
    // }
    // let res = [];
    // for (key in anagrams) {
    //     let value = anagrams[key].split(",")
    //     res.push(value)
    // }
    // return res;
    let obj = {};
    for (let str of strs) {
        let letters = str.split("").sort().join("");
        obj[letters] ? obj[letters].push(str) : obj[letters] = [str];
    }
    return Object.values(obj);
};