The titular question is associated to the following problem: https://i.gyazo.com/07b7dde7efe1df0b7ae9550317851fda.png
标题问题与以下问题有关:https://i.gyazo.com/07b7efe1df0b7ae9550317851fda.png。
And a more detailed explanation of the titular problem can be provided but I can't post more than two links so if someone replies and asks for it I can provide it to you!
并且可以提供一个更详细的标题问题的解释，但我不能张贴超过两个链接，所以如果有人回复和要求，我可以提供给你!
To start, I understand that the whole question is based upon the idea of the tortoise and hare algorithm for cycle detection (I would link the Wikipedia page, but I don't have enough reputation). I also understand that the existence of a loop is proven by the tortoise and hare 'meeting up' with each other after leaving the first node. I also know that where they meet up for the second time in the second phase of the algorithm is indicative of exactly where the loop begins.
首先，我理解整个问题是基于乌龟和兔子算法的循环检测思想(我会链接*的页面，但我没有足够的声誉)。我也明白，在离开第一个节点后，乌龟和兔子“相遇”证明了循环的存在。我还知道，在算法的第二阶段，它们第二次相遇的地方表明了循环的确切起点。
Unfortunately, I simply can't wrap my head around relating this/these facts to the question given and how to create an algorithm for it.
不幸的是，我不能把这些事实和所给的问题以及如何创建算法联系起来。
Any help is greatly appreciated!
非常感谢您的帮助!
1 个解决方案
#1
0
No idea how you're supposed to make an algorithm for it, but it seems like simple modulo math. T(x) = x mod 5 and H(x) = 2x mod 5. You're asked to solve for when T(x) = H(x). Since both expression are modulo 5, you know they're equal when 2x - x = 5k where k is some integer.
不知道如何为它建立一个算法，但它看起来很简单。T(x) = x mod 5和H(x) = 2x mod 5。要求解T(x) = H(x)因为这两个表达式都是模5，所以当2x - x = 5k时它们是相等的，k是一个整数。
#1
0
No idea how you're supposed to make an algorithm for it, but it seems like simple modulo math. T(x) = x mod 5 and H(x) = 2x mod 5. You're asked to solve for when T(x) = H(x). Since both expression are modulo 5, you know they're equal when 2x - x = 5k where k is some integer.
不知道如何为它建立一个算法，但它看起来很简单。T(x) = x mod 5和H(x) = 2x mod 5。要求解T(x) = H(x)因为这两个表达式都是模5，所以当2x - x = 5k时它们是相等的，k是一个整数。