Longest Common Subsequence: Difference between revisions

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(Created page with "{{DISPLAYTITLE:Longest Common Subsequence (Longest Common Subsequence)}} == Description == The longest common subsequence (LCS) problem is the problem of finding the longest subsequence common to all sequences in a set of sequences (often just two sequences). == Related Problems == Subproblem: Longest Common Substring with don't cares == Parameters == <pre>$n$: length of the longer input string $m$: length of the shorter input string $r$: length of the LCS $s...")
 
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== Parameters ==  
== Parameters ==  


<pre>$n$: length of the longer input string
$n$: length of the longer input string
 
$m$: length of the shorter input string
$m$: length of the shorter input string
$r$: length of the LCS
$r$: length of the LCS
$s$: size of the alphabet
$s$: size of the alphabet
$p$: the number of dominant matches (AKA number of minimal candidates), i.e. the total number of ordered pairs of positions at which the two sequences match</pre>
 
$p$: the number of dominant matches (AKA number of minimal candidates), i.e. the total number of ordered pairs of positions at which the two sequences match


== Table of Algorithms ==  
== Table of Algorithms ==  
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Currently no algorithms in our database for the given problem.
Currently no algorithms in our database for the given problem.


== Time Complexity graph ==  
== Time Complexity Graph ==  


[[File:Longest Common Subsequence - Time.png|1000px]]
[[File:Longest Common Subsequence - Time.png|1000px]]
== Space Complexity graph ==
[[File:Longest Common Subsequence - Space.png|1000px]]
== Pareto Decades graph ==
[[File:Longest Common Subsequence - Pareto Frontier.png|1000px]]


== Reductions FROM Problem ==  
== Reductions FROM Problem ==  

Latest revision as of 09:05, 28 April 2023

Description

The longest common subsequence (LCS) problem is the problem of finding the longest subsequence common to all sequences in a set of sequences (often just two sequences).

Related Problems

Subproblem: Longest Common Substring with don't cares

Parameters

$n$: length of the longer input string

$m$: length of the shorter input string

$r$: length of the LCS

$s$: size of the alphabet

$p$: the number of dominant matches (AKA number of minimal candidates), i.e. the total number of ordered pairs of positions at which the two sequences match

Table of Algorithms

Currently no algorithms in our database for the given problem.

Time Complexity Graph

Longest Common Subsequence - Time.png

Reductions FROM Problem

Problem Implication Year Citation Reduction
UOV If: to-time: $O((nm)^{({1}-\epsilon)})$, where $|x| = O(nd)$ and $|y| = O(md)$
Then: from-time: $O((nm)^{({1}-\epsilon/{2})})$
2015 https://arxiv.org/pdf/1502.01063.pdf link

References/Citation

https://link.springer.com/chapter/10.1007/978-3-662-43948-7_4