feat: search-in-rotated-sorted-array

Author: HodaeSsi

search-in-rotated-sorted-array/HodaeSsi.py

@@ -0,0 +1,44 @@
+from typing import List
+
+# 시간 복잡도 : O(log n) (* 최대 세번의 이진 탐색 수행)
+# 공간 복잡도 : O(1)
+class Solution:
+	def find_pivot_idx(self, src_list: List[int], start_idx: int, end_idx: int) -> int:
+		if start_idx == end_idx:
+			return start_idx
+		mid_idx = (start_idx + end_idx) // 2
+		if src_list[mid_idx] > src_list[end_idx]:
+			return self.find_pivot_idx(src_list, mid_idx + 1, end_idx)
+		else:
+			return self.find_pivot_idx(src_list, start_idx, mid_idx)
+		
+
+	def find_target_idx(self, src_list: List[int], start_idx: int, end_idx: int, target) -> int:
+		if start_idx > end_idx:
+			return -1
+		if start_idx == end_idx:
+			if src_list[start_idx] == target:
+				return start_idx
+			else:
+				return -1
+
+		mid_idx = (start_idx + end_idx) // 2
+		if src_list[mid_idx] == target:
+			return mid_idx
+		elif src_list[mid_idx] > target:
+			return self.find_target_idx(src_list, start_idx, mid_idx - 1, target)
+		else:
+			return self.find_target_idx(src_list, mid_idx + 1, end_idx, target)
+			
+
+	def search(self, nums: List[int], target: int) -> int:
+		if nums[0] > nums[len(nums) - 1]:
+			pivot_idx = self.find_pivot_idx(nums, 0, len(nums) - 1)
+			left = self.find_target_idx(nums, 0, pivot_idx - 1, target)
+			if left != -1:
+				return left
+			else:
+				return self.find_target_idx(nums, pivot_idx, len(nums) - 1, target)
+		else:
+			return self.find_target_idx(nums, 0, len(nums) - 1, target)
+