https://leetcode.com/problems/shifting-letters-ii

medium/shifting_letters_2.py

@@ -0,0 +1,29 @@
+# https://leetcode.com/problems/shifting-letters-ii
+
+from typing import List
+
+class Solution:
+    def convert(self, s: str, shift: int) -> str:
+        return chr(
+            (
+                (ord(s) - ord('a') + shift) % 26
+            ) + ord('a')
+        )
+
+    def shiftingLetters(self, s: str, shifts: List[List[int]]) -> str:
+        l = len(s)
+        shifting = [0] * (l + 1)
+        for [start, end, direction] in shifts:
+            if direction == 0:
+                shifting[start] -= 1
+                shifting[end + 1] += 1
+            else:
+                shifting[start] += 1
+                shifting[end + 1] -= 1
+        shift = 0
+        result = []
+        for i in range(len(s)):
+            shift += shifting[i]
+            result.append(self.convert(s[i], shift))
+        return ''.join(result)
+