javascript内置split函数的Big O

本文介绍了javascript内置split函数的Big O的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

示例:

var string = "abcde"; var array = string.split(""); // array = ["a", "b", "c", "d", "e"]

此拆分功能的摊销运行时间是多少?另外，如何在javascript中查看此类内置函数的源代码?

What is the amortized running time of this split function? Also, how do I view source code of such built-in functions in javascript?

推荐答案

使用空的定界符参数，split本质上等效于:

With an empty delimiter argument, split is essentially equivalent to:

var len = string.length; var result = Array(len) for (i = 0; i < len; i++) { result[i] = string[i]; }

这是O(len).

使用定界符，它将变为O(string.length * delimiter.length)，因为在循环的每个步骤中，它都必须测试delimiter是否匹配.

With a delimiter, it becomes O(string.length * delimiter.length), because at each step in the loop it has to test whether there's a match for delimiter.