Tower of Hanoi: Difference between revisions

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== Parameters ==  
== Parameters ==  


n: number of discs
$n$: number of discs


p: number of pegs
$p$: number of pegs


== Table of Algorithms ==  
== Table of Algorithms ==  
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| [[Iteration based (Tower of Hanoi Tower of Hanoi)|Iteration based]] || 1883 || $O({2}^n)$ || $O(n)$ auxiliary || Exact || Deterministic ||   
| [[Iteration based (Tower of Hanoi Tower of Hanoi)|Iteration based]] || 1883 || $O({2}^n)$ || $O(n)$ || Exact || Deterministic ||   
|-
|-
| [[Recursion based (Tower of Hanoi Tower of Hanoi)|Recursion based]] || 1940 || $O({2}^n)$ || $O(n*log n)$ auxiliary || Exact || Deterministic ||   
| [[Recursion based (Tower of Hanoi Tower of Hanoi)|Recursion based]] || 1940 || $O({2}^n)$ || $O(n \log n)$ || Exact || Deterministic ||   
|-
|-
| [[Non-recursion based (Tower of Hanoi Tower of Hanoi)|Non-recursion based]] || 1940 || $O({2}^n)$ || $O(n)$ auxiliary || Exact || Deterministic ||   
| [[Non-recursion based (Tower of Hanoi Tower of Hanoi)|Non-recursion based]] || 1940 || $O({2}^n)$ || $O(n)$ || Exact || Deterministic ||   
|-
|-
| [[Gray-code based (Tower of Hanoi Tower of Hanoi)|Gray-code based]] || 1940 || $O({2}^n)$ || $O(n)$ auxiliary || Exact || Deterministic ||   
| [[Gray-code based (Tower of Hanoi Tower of Hanoi)|Gray-code based]] || 1940 || $O({2}^n)$ || $O(n)$ || Exact || Deterministic ||   
|-
|-
| [[Hanoi graph (Tower of Hanoi Tower of Hanoi)|Hanoi graph]] || 2008 || $O({2}^n)$ ||  || Exact || Deterministic || [https://books.google.com/books/about/Topics_in_Graph_Theory.html?id=pSv3XotPCQgC Time]
| [[Hanoi graph (Tower of Hanoi Tower of Hanoi)|Hanoi graph]] || 2008 || $O({2}^n)$ ||  || Exact || Deterministic || [https://books.google.com/books/about/Topics_in_Graph_Theory.html?id=pSv3XotPCQgC Time]
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[[File:Tower of Hanoi - Time.png|1000px]]
[[File:Tower of Hanoi - Time.png|1000px]]
== Space Complexity Graph ==
[[File:Tower of Hanoi - Space.png|1000px]]
== Time-Space Tradeoff ==
[[File:Tower of Hanoi - Pareto Frontier.png|1000px]]

Latest revision as of 10:12, 28 April 2023

Description

The Tower of Hanoi puzzle consists of $n$ discs, no two of the same size, stacked on $p \geq 3$ vertical pegs, in such a way that no disc lies on top of a smaller disc. A permissible $move$ is to take the top disc from one of the pegs and move it to one of the other pegs, as long as it is not placed on top of a smaller disc. Initially, they are all stacked on the first peg. The goal is to end up with them all stacked on the last peg.

Parameters

$n$: number of discs

$p$: number of pegs

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Iteration based 1883 $O({2}^n)$ $O(n)$ Exact Deterministic
Recursion based 1940 $O({2}^n)$ $O(n \log n)$ Exact Deterministic
Non-recursion based 1940 $O({2}^n)$ $O(n)$ Exact Deterministic
Gray-code based 1940 $O({2}^n)$ $O(n)$ Exact Deterministic
Hanoi graph 2008 $O({2}^n)$ Exact Deterministic Time

Time Complexity Graph

Tower of Hanoi - Time.png