二分查找 (Binary Search)

概述

难度：简单 (Easy)
分类：Search / 查找

二分查找是一种在有序数组中查找目标元素的搜索算法。

Binary search is a search algorithm that finds the position of a target value within a sorted array.

算法原理

中文：通过比较数组中间元素与目标值，每次将搜索范围缩小一半。

English: By comparing the middle element with the target, the search range is halved each time.

复杂度分析

代码实现

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

每日练习

1. 完成算法实现
2. 分析算法复杂度
3. 思考：算法的适用场景和局限性

相关阅读：算法专栏

💡 学习建议：算法学习重在理解思想，多写多练是关键。 💡 Learning tip: Algorithm learning is about understanding the core idea. Practice makes perfect.