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Binary Search in Sorted Array
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Binary Search in Sorted Array

EasyPython

Problem

At Stripe, a service stores sorted numeric IDs in memory and needs fast lookups. Implement binary search to find the index of a target value in a sorted array.

Given a sorted list of integers nums in ascending order and an integer target, return the index of target if it exists. Otherwise, return -1.

Formal Specification

  • Input: nums (list of integers sorted in ascending order), target (integer)
  • Output: Integer index of target, or -1 if not found

Constraints

  • 1 <= len(nums) <= 10^5
  • -10^9 <= nums[i], target <= 10^9
  • nums is sorted in ascending order
  • All values in nums are distinct

Function Signature

def binary_search(nums, target):
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