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万字总结!超详细!
    查看>>
    Mysql下载以及安装(新手入门,超详细)
    查看>>
    MySQL不会性能调优?看看这份清华架构师编写的MySQL性能优化手册吧
    查看>>
    MySQL不同字符集及排序规则详解:业务场景下的最佳选
    查看>>
    Mysql不同官方版本对比
    查看>>
    MySQL与Informix数据库中的同义表创建:深入解析与比较
    查看>>
    mysql与mem_细说 MySQL 之 MEM_ROOT
    查看>>
    MySQL与Oracle的数据迁移注意事项,另附转换工具链接
    查看>>
    mysql丢失更新问题
    查看>>
    MySQL两千万数据优化&迁移
    查看>>
    MySql中 delimiter 详解
    查看>>
    MYSQL中 find_in_set() 函数用法详解
    查看>>
    MySQL中auto_increment有什么作用?(IT枫斗者)
    查看>>
    MySQL中B+Tree索引原理
    查看>>
    mysql中cast() 和convert()的用法讲解
    查看>>
    mysql中datetime与timestamp类型有什么区别
    查看>>
    MySQL中DQL语言的执行顺序
    查看>>
    mysql中floor函数的作用是什么?
    查看>>
    MySQL中group by 与 order by 一起使用排序问题
    查看>>
    mysql中having的用法
    查看>>