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.
class Solution:
def signature(self, string):
len_signature = ord('z') - ord('a') + 1
count_chars = [0] * len_signature
for char in string:
count_chars[ord(char) - ord('a')] += 1
signature = ""
for char_ord in range(ord('a'), ord('z') + 1):
signature += chr(char_ord) * count_chars[char_ord - ord('a')]
return signature
def groupAnagrams(self, strs: List[str]) -> List[List[str]]:
anagrams = {}
for string in strs:
signature = self.signature(string)
if signature not in anagrams:
anagrams[signature] = []
anagrams[signature].append(string)
return anagrams.values()For each string build a ordered signature made of every character in it. For example the signature of "zdwwaa" is "aadwwz". Then group in a map each string by its signature.