group anagrams

Author: sonjh1217

group-anagrams/sonjh1217.swift

@@ -0,0 +1,18 @@
+class Solution {
+    func groupAnagrams(_ strs: [String]) -> [[String]] {
+        var stringsByCount = [[Int]: [String]]()
+        
+        strs.map { str in
+            var countsByAlphabet = Array(repeating: 0, count: 26)
+            for char in str.unicodeScalars {
+                countsByAlphabet[Int(char.value) - 97] += 1
+            }
+            stringsByCount[countsByAlphabet, default: []].append(str)
+        }
+        
+        return Array(stringsByCount.values)
+    }
+    //시간 O(n*L) L=string들의 평균 길이
+    //공간 O(n*L)
+}
+