博客
关于我
C++折半查找的实现
阅读量:745 次
发布时间:2019-03-22

本文共 2235 字,大约阅读时间需要 7 分钟。

C++折半查找法的实现与理解

折半查找法,也称二分查找,是一种高效的查找算法,特别适用于已排序的数组。它通过不断缩小查找范围来快速定位目标元素。以下是关于折半查找法的详细实现和理解。

Fold-Halving Search in C++: Implementation and Explanation

Fold-halving, or binary search, is an efficient searching algorithm primarily used for sorted arrays. By repeatedly dividing the search interval in half, this method allows for rapid location of a target element. Below is the detailed implementation and explanation of fold-halving in C++.

Sorting: The Initial Step

Before performing fold-halving, the array must be sorted. The given array is sorted to facilitate the fold-halving process:

arr = {1,2,3,4,5,6,7,8,9,10,11}

Key Steps in Fold-Halving

  • Initialization:

    • Define low as the initial smallest index (0).
    • Define high as the initial largest index (10).
    • Calculate mid, the middle index of the array.
  • Loop Until mid is Within Bounds:

    • While low is less than or equal to high.
    • Compute mid as the average of low and high, using integer division for exact mid-point calculation.
    • Compare the target key with the element at mid.
  • Comparison and Range Adjustment:

    • If key equals arr[mid], return mid as the target's position.
    • If key is greater than arr[mid], set low to mid + 1 and adjust the search interval to [mid + 1, high].
    • If key is less than arr[mid], set high to mid - 1 and adjust the search interval to [low, mid - 1].
  • Example: Finding Target Element 7

  • Initial Setup:

    • low = 0, high = 10, mid = 5.
    • Target key = 7.
  • First Comparison:

    • arr[5] is 7. Return mid = 5.
  • Handling Edge Cases

    • Empty Array: Handle array size checks to avoid invalid operations.
    • Single Element Array: Directly compare the single element with the key.
    • Multiple Occurrences of Key: If the key is present multiple times, ensure the loop continues until all possible locations are exhausted.

    Cost of Fold-Halving

    The time complexity of fold-halving is O(log n), making it significantly more efficient than linear search for large arrays. The space complexity is O(1) as no additional data structures are used.

    Conclusion

    Fold-halving is an essential algorithm for efficient array searching. By leveraging sorted data and dividing the search space, this method quickly pinpoints the target element, demonstrating its efficiency and reliability in various applications.

    转载地址:http://tnxwk.baihongyu.com/

    你可能感兴趣的文章
    mysql的全文检索的方法
    查看>>
    MySQL的函数
    查看>>
    mysql的函数DATE_ADD()
    查看>>
    mysql的函数操作
    查看>>
    mysql的分类排名_mysql高低排名
    查看>>
    Mysql的分表设计方法 (水平分表和垂直分表)
    查看>>
    mysql的分页查询limit关键字
    查看>>
    MySql的创建数据表、约束、外键约束的创建修改删除、级联操作
    查看>>
    MySQL的删除修改的实验目的_基础篇 - 数据库及表的修改和删除
    查看>>
    MySQL的四大隔离级别,你都知道哪些?
    查看>>
    MySQL的四种事务隔离级别
    查看>>
    MySQL的基本命令
    查看>>
    Mysql的备份与恢复类型
    查看>>
    mysql的大小写对性能的影响问题
    查看>>
    mysql的密码管理、mysql初始密码查找、密码修改、mysql登录
    查看>>
    mysql的常见八股文面试题
    查看>>
    MySQL的常见命令
    查看>>
    mysql的引擎以及优缺点_MySQL有哪些存储引擎,各自的优缺点,应用场景-阿里云开发者社区...
    查看>>
    MySQL的操作:
    查看>>
    mysql的数据类型有哪些?
    查看>>