Search in Rotated Sorted Array

Problem Statement
You are given an integer array nums sorted in ascending order (with distinct values), and it might have been rotated at an unknown pivot index. Write a function that searches for a given target value and returns its index if found, otherwise return -1. Your solution must achieve O(log n) time complexity using a modified binary search approach.[1][2][7]

Input/Output Examples

• Input: nums = [4,5,6,7,0,1,2], target = 0 → Output: 4 (target at index 4).[2]
• Input: nums = [4,5,6,7,0,1,2], target = 3 → Output: -1 (target not found).[1]
• Input: nums = [1], target = 0 → Output: -1.[7]

Constraints

• 1 <= nums.length <= 5000[2]
• -10^4 <= nums[i] <= 10^4[7]
• All nums[i] are unique (no duplicates).[1][2]
• nums was originally sorted in ascending order.[7][1]