First Unique Character in a String

arai60/first-unique-character-in-a-string/step1.py

@@ -0,0 +1,17 @@
+"""
+2m30s
+
+ループ1回で終わらせたいとは思ったが、2回にしてしまったほうがシンプルになると思ったのでそうした
+"""
+
+from collections import defaultdict
+
+class Solution:
+    def firstUniqChar(self, s: str) -> int:
+        char_count = defaultdict(int)
+        for c in s:
+            char_count[c] += 1
+        for i, c in enumerate(s):
+            if char_count[c] == 1:
+                return i
+        return -1

arai60/first-unique-character-in-a-string/step2.py

@@ -0,0 +1,17 @@
+"""
+割とみんな同じような解き方。
+
+char_count → char_to_count
+"""
+
+from collections import defaultdict
+
+class Solution:
+    def firstUniqChar(self, s: str) -> int:
+        char_to_count = defaultdict(int)
+        for c in s:
+            char_to_count[c] += 1
+        for i, c in enumerate(s):
+            if char_to_count[c] == 1:
+                return i
+        return -1