LC 49 Group Anagrams

Implementation

// 49. Group Anagrams
// Given an array of strings strs, group the anagrams together. You can return the answer in any order.

// Example 1:
// Input: strs = ["eat","tea","tan","ate","nat","bat"]
// Output: [["bat"],["nat","tan"],["ate","eat","tea"]]

// Explanation:
// There is no string in strs that can be rearranged to form "bat".
// The strings "nat" and "tan" are anagrams as they can be rearranged to form each other.
// The strings "ate", "eat", and "tea" are anagrams as they can be rearranged to form each other.
// 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.

const groupAnagrams = (strs) => {
 const map = new Map();

    for (const str of strs) {
        const freq = new Array(26).fill(0);

        for (const ch of str) {
            freq[ch.charCodeAt(0) - 97]++;
        }

        const key = freq.join('');

        if (!map.has(key)) {
            map.set(key, []);
        }
        map.get(key).push(str);
    }

    return [...map.values()];
};

console.log(groupAnagrams(["eat","tea","tan","ate","nat","bat"]));
console.log(groupAnagrams([""]));
console.log(groupAnagrams(["a"]));

Tests

// Test stub for 05.49.GroupAnagrams

describe('05.49.GroupAnagrams', () => {
  it('should have a test stub', () => {
    expect(true).toBe(true);
  });
});