Group Anagrams

group_anagrams.js

/*
INPUT
anagrams(['xxy', 'cab', 'bca', 'cab', 'bac', 'baa', 'abb', 'dash', 'shad'])

OUTPUT
[
 ['xxy'],
 ['cab', 'bca’, 'bac'],
 ['dash', 'shad'],
 ['abb'],
 ['baa'],
]
anagrams are words that can be rearranged to become the same word.

Group strings that are anagram of each other into a list without duplicate.
*/

const sortString = (str) => {
  return str.split("").sort().join("");
}
const anagrams = (words) => {
  if (!Array.isArray(words)) {
    return null;
  }
  const uniqeArr = [... new Set(words)];
  const results = {};
  uniqeArr.forEach((el) => {
    let sortedString = sortString(el);
    if(results.hasOwnProperty(sortedString)) {
      results[sortedString].unshift(el);
    } else {
      results[sortedString] = [el];
    }
    
  })
  return Object.values(results);
}

const groupedAnagrams = anagrams(['xxy', 'cab', 'bca', 'baa', 'abb', 'cab', 'bac', 'dash', 'shad']);
console.log(groupedAnagrams);

const testCase1 = anagrams([]);
const testCase2 = anagrams('xxy', 'cab', 'sos');
const testCase3 = anagrams('sos');
const testCase4 = anagrams(['sos', 'lol', { sos: 'sos'}]);
const testCase5 = anagrams(['sos', 'lol', 'cab', '', 123]);
const testCase6 = anagrams(777);
const testCase7 = anagrams(['sos', 'lol', 'cab', 'zsc', 'scz', 'csz']);