关于for循环的问题 [英] A question on for loop
问题描述
这两个版本的代码会有效吗？假设所有变量都已初始化。我认为一个更好的问题可能是两个版本的效果有所不同吗？
版本1：
for（; i< R; i ++）{...}
版本2：
for（; i< R; ++ i）{...}
Would there be any difference in effect in these two versions of code? Just assume that all variables are initialized. I think a better question might be is there a case where the effects of two versions differ?
VERSION 1:
for(; i < R; i++) { ... }
VERSION 2:
for(; i < R; ++i) { ... }
推荐答案
文章< 87 ************ @ student.uts.edu.au>，
Logan Lee< Lo ********* @ student.uts.edu.auwrote：
In article <87************@student.uts.edu.au>,
Logan Lee <Lo*********@student.uts.edu.auwrote:
>会不会有任何区别这两个版本的代码效果如何？只是
假设所有变量都已初始化。我认为一个更好的问题可能是两个版本的效果有何不同？
版本1：
（; i< R; i ++）{。 ..}
版本2：
for（; i< R; ++ i）{...}
>Would there be any difference in effect in these two versions of code? Just
assume that all variables are initialized. I think a better question might be
is there a case where the effects of two versions differ?
VERSION 1:
for(; i < R; i++) { ... }
VERSION 2:
for(; i < R; ++i) { ... }
不，他们是一样的。
- Richard
-
：wq
No, they''re the same.
-- Richard
--
:wq
Logan Lee< Lo ********* @ student.uts.edu.auwrites：
Logan Lee <Lo*********@student.uts.edu.auwrites:
这两个版本的代码在效果上有什么不同？
假设所有变量都已初始化。我认为更好的问题可能是两个版本
的效果有什么不同？
版本1： for（; i< R; i ++）{...}
VERSION 2：for（; i< R; ++ i）{...}
Would there be any difference in effect in these two versions of code?
Just assume that all variables are initialized. I think a better
question might be is there a case where the effects of two versions
differ?
VERSION 1: for(; i < R; i++) { ... }
VERSION 2: for(; i < R; ++i) { ... }
这些循环是等效的。此外，对于许多（大多数？）
编译器，生成的代码将是相同的。
-
Ben Pfaff
< a rel =nofollowhref =http://benpfaff.orgtarget =_ blank> http://benpfaff.org
On星期二，2007年12月18日09:09:09 +1100，Logan Lee
< Lo ********* @ student.uts.edu.auwrote：
On Tue, 18 Dec 2007 09:09:09 +1100, Logan Lee
<Lo*********@student.uts.edu.auwrote:
>这两个版本的代码在效果上会有什么不同吗？假设所有变量都已初始化。我认为一个更好的问题可能是两个版本的效果有所不同吗？
版本1：
（（i< R; i ++）{...} <版本2：
for（; i< R; ++ i）{...}
>Would there be any difference in effect in these two versions of code? Just assume that all variables are initialized. I think a better question might be is there a case where the effects of two versions differ?
VERSION 1:
for(; i < R; i++) { ... }
VERSION 2:
for(; i < R; ++i) { ... }
首先，写作一个for循环，然后没有初始化变量i在
开头是一个可憎的做法。 for的全部意义。就是那个
3个控制元素被放置在循环的顶部，所以它确实是清楚发生了什么。如果我必须从那里找到
，那么i的初始值应该是什么，这使得代码更难以阅读和维护。我不知道这种做法出现在哪里
但不管它在哪里都应该被劝阻。如果你打算
取决于我在其他地方进行初始化，你可以将
写成循环作为while结构。
至于V1与V2，它们是相同的。
First, writing a for loop and then not initializing variable i in the
beginning is a detestable practice. The whole point of "for" is that
the 3 control elements are placed at the top of the loop so it is
clear exactly what is going on. If I have to go up from there to find
out what the initial value of i is supposed to be it makes the code
harder to read and maintain. I don''t know where this practice arose
but it should be discouraged wherever it is found. If you are going to
depend on i being initialized somewhere else, you may as well have
written the loop as a while construct.
As for V1 vs. V2, they are the same.
这篇关于关于for循环的问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
