CodeEasy v0.1

Binary Search

Easy Subject: Binary Search
Time Complexity
O(log N)
Space Complexity
O(1)

Problem Description

Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target in nums. If target exists, then return its index. Otherwise, return -1.

Optimal Solution

Python 
def search(nums, target):
    left, right = 0, len(nums) - 1
    while left <= right:
        mid = left + (right - left) // 2
        if nums[mid] == target:
            return mid
        elif nums[mid] < target:
            left = mid + 1
        else:
            right = mid - 1
    return -1