grounp-anagram solution (py, ts)

Author: hi-rachel

group-anagrams/hi-rachel.py

@@ -0,0 +1,14 @@
+# TC O(N * K log K), SC O(N * K)
+
+from collections import defaultdict
+
+class Solution:
+    def groupAnagrams(self, strs: List[str]) -> List[List[str]]:
+        anagram_map = defaultdict(list)
+
+        for word in strs:
+            key = ''.join(sorted(word))
+            anagram_map[key].append(word)
+
+        return list(anagram_map.values())
+    

group-anagrams/hi-rachel.ts

@@ -0,0 +1,51 @@
+// TC O(N * K log K), N: 단어 수, K: 평균 단어 길이, 각 단어를 정렬
+// SC O(N * K)
+
+/**
+ * Array.from() => 이터러블 -> 일반 배열로 변환
+ */
+function groupAnagrams(strs: string[]): string[][] {
+  const anagramMap: Map<string, string[]> = new Map();
+
+  for (const word of strs) {
+    const key = word.split("").sort().join("");
+    const group = anagramMap.get(key) || [];
+    group.push(word);
+    anagramMap.set(key, group);
+  }
+  return Array.from(anagramMap.values());
+}
+
+/**
+ * reduce 풀이
+ */
+// function groupAnagrams(strs: string[]): string[][] {
+//   const anagramMap = strs.reduce((map, word) => {
+//     const key = word.split("").sort().join("");
+//     if (!map.has(key)) {
+//       map.set(key, []);
+//     }
+//     map.get(key).push(word);
+//     return map;
+//   }, new Map<string, string[]>());
+
+//   return Array.from(anagramMap.values());
+// }
+
+/**  간결한 버전
+ * x ||= y (ES2021)
+ * x가 falsy 값이면 y를 할당
+ * JS에서 falsy 값 = false, 0, '', null, undefined, NaN
+ *
+ * Object.values() => 객체의 값들만 배열로 추출할때 사용
+ */
+// function groupAnagrams(strs: string[]): string[][] {
+//     const anagramMap: {[key: string]: string[]} = {};
+
+//     strs.forEach((word) => {
+//         const key = word.split('').sort().join('');
+//         (anagramMap[key] ||= []).push(word);
+//     });
+
+//     return Object.values(anagramMap);
+// }