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computability halting-problem

Brent

2,477

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92 votes

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Why are some programming languages "faster" or "slower" than others?

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evil_potato

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74 votes

1 answer

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Raphael♦

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73 votes

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Express boolean logic operations in zero-one integer linear programming (ILP)

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52 votes

8 answers

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corium

869

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52 votes

6 answers

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Keeping a String Secret in (Open) Source Code

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50 votes

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What exactly is the semantic difference between set and type?

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49 votes

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Show that { xy ∣ |x| = |y|, x ≠ y } is context-free

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49 votes

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5k views

What is the meaning of $O(m+n)$?

terminology asymptotics mathematical-analysis landau-notation

Frank

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48 votes

10 answers

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O(·) is not a function, so how can a function be equal to it?

asymptotics landau-notation notation

doubleE

591

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45 votes

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terminology computability undecidability rice-theorem

MathematicalOrchid

857

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45 votes

2 answers

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How to show that a function is not computable?

computability proof-techniques undecidability reference-question

user5507

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Raphael♦

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41 votes

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Christian

519

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35 votes

6 answers

8k views

Do lossless compression algorithms reduce entropy?

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robert

453

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32 votes

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algorithms fourier-transform divide-and-conquer

lars

483

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32 votes

7 answers

9k views

What are the simplest examples of programs that we do not know whether they terminate?

computability turing-machines halting-problem

MaiaVictor

4,017

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30 votes

2 answers

5k views

Is Lambda Calculus purely syntactic?

lambda-calculus functional-programming

Neil

431

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30 votes

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Are algorithms (and efficiency in general) getting less important?

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843

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30 votes

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bek

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30 votes

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Koray Tugay

318

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29 votes

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Longest Repeated (Scattered) Subsequence in a String

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Sekti

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29 votes

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270k

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28 votes

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formal-languages context-free formal-grammars proof-techniques reference-question

D.W.♦

141k

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28 votes

3 answers

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When is the minimum spanning tree for a graph not unique

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Keiwan

467

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26 votes

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Is the language of pairs of words of equal length whose hamming distance is 2 or greater context-free?

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Robert777

737

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24 votes

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What is the formal, rigorous definition of a programming language?

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user107952

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Why are NP-complete problems so different in terms of their approximation?

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GregRos

505

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21 votes

2 answers

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Do the minimum spanning trees of a weighted graph have the same number of edges with a given weight?

graphs spanning-trees weighted-graphs

Aden Dong

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asked Jun 2, 2012 at 22:25

21 votes

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Why, really, is the Halting Problem so important?

Why are some programming languages "faster" or "slower" than others?

Language theoretic comparison of LL and LR grammars

Express boolean logic operations in zero-one integer linear programming (ILP)

How to prove a language is regular?

Keeping a String Secret in (Open) Source Code

What exactly is the semantic difference between set and type?

Show that { xy ∣ |x| = |y|, x ≠ y } is context-free

What is the meaning of $O(m+n)$?

O(·) is not a function, so how can a function be equal to it?

Perplexed by Rice's theorem

How to show that a function is not computable?

What are common techniques for reducing problems to each other?

How does a computer work?

Do lossless compression algorithms reduce entropy?

Show how to do FFT by hand

What are the simplest examples of programs that we do not know whether they terminate?

Is Lambda Calculus purely syntactic?

Are algorithms (and efficiency in general) getting less important?

Optimization version of decision problems

Is Morse Code binary, ternary or quinary?

Longest Repeated (Scattered) Subsequence in a String

Asymptotics of the number of words in a regular language of given length

How to prove that a language is context-free?

When is the minimum spanning tree for a graph not unique

Is the language of pairs of words of equal length whose hamming distance is 2 or greater context-free?

What is the formal, rigorous definition of a programming language?

Why are NP-complete problems so different in terms of their approximation?

Do the minimum spanning trees of a weighted graph have the same number of edges with a given weight?

Why is this code uniquely decodable?