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Questions tagged [heaps-algorithm]

Heap's algorithm generates all possible permutations of n objects. The algorithm minimizes movement: it generates each permutation from the previous one by interchanging a single pair of elements

See Wikipedia.

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Heap's algorithm for permutations

I'm preparing for interviews and I'm trying to memorize Heap's algorithm: procedure generate(n : integer, A : array of any): if n = 1 then output(A) else for i := 0; i < n; i += 1 do generate(n - 1, A) …
Dean
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Heap's algorithm permutation generator

I need to iterate over permutations of a tuple of integers. The order has to be generated by swapping a pair of elements at each step. I found the Wikipedia article (http://en.wikipedia.org/wiki/Heap%27s_algorithm) for Heap's algorithm, which is…
EvenAdam
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How to iterate over all unique permutations of a sequence in Rust?

Given a list of values, such as vec![0, 0, 1, 2], I would like to create an iterator that generates all of its unique permutations. That is, [0, 0, 1, 2] [0, 0, 2, 1] [0, 1, 0, 2] [0, 1, 2, 0] [0, 2, 0, 1] [0, 2, 1, 0] [1, 0, 0, 2] [1, 0, 2, 0] [1,…
Christopher Rybicki
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Permutations via Heap's algorithm with a mystery comma

I have spent the whole day (finally) wrapping my head around a permutation algorithm in practice for an admissions application on Friday. Heap's algorithm seemed most simple and elegant to me. here is an example of it:…
zazou
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C# implementation of Heap's algorithm doesn't work

I've attempted to write an implementation of Heap's Algorithm in C# which isn't working correctly. I'm trying to create a general-purpose implementation that will find all permutations of a string, and add them to a list. I'm starting out like…
alex
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Generating k permutations from n in C

I basically need the equivalent result of the following Python itertools command in C: a = itertools.permutations(range(4),2)) Currently my process involves first "choosing" 5 elements from 10 then generating permutations for those 5 elements as…
Siddharth Chabra
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Heap's algorithm in Clojure (can it be implemented efficiently?)

Heap's algorithm enumerates the permutations of an array. Wikipedia's article on the algorithm says that Robert Sedgewick concluded the algorithm was ``at that time the most effective algorithm for generating permutations by computer,'' so naturally…
Ray Toal
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Heap's algorithm

Trying to reproduce Heap's algorithm, for generating all possible permutations of an array of integers, but I can't solve it for other integers than three. Heap's algorithm from Wikipedia: procedure generate(N : integer, data : array of any): if N…
user2069136
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Heap's algorithm time complexity

can anyone tell me what exactly is the time complexity of this Heap's algorithm shown in wikipedia, https://en.wikipedia.org/wiki/Heap%27s_algorithm ? I searched several websites and the answers are all vague, some of them say the time complexity is…
nightowl_nicky
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Why does duplications happen in Heap's algorithm

I want to get all permutations from elements of array. Source array is very simple: $arr = [ 1,2,3,4 ]; I wrote the code for implement Heap's algorithm, private function mixture( $size, array $collection ) { $permutations = []; $offset =…
Kudryavtsev Maxim
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Creating arrays for permutations within a subsection of a list

So I have a list: a 25 b 18 c 18 d 18 e 14 f 14 g 12 ... and so on For each number that matches, I have to get every permutation of the identifier. The lists I would need from my example would be as…
Display Name
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Modifying Heap's Algorithm for Generating Permutations

Heap's algorithm is a systematic way to cycle through all permutations of N elements "one exchange at a time". For odd N, it's especially neat because the final permutation seems to be only one exchange different from the first permutation. But,…
bobuhito
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Generate Permutations using Heap's Algorithm

I am trying to generate all permutations for an array using the Heap's algorithm that I found in wikipedia. This is what I tried so far: n <- 3 A <- c(1, 2, 3) perm <- function(n, A) { if (n == 1) print(perm) for (i in length(A)) perm(n,…
aycee
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Heap's algorithm checking for odd and even

can someone explain why does Heap's Algorithm uses a condition statement checking for K whether it is even or odd and the swaps are different in each one? i can't find any intuitive explanation on the Internet this code is from Wikipedia procedure…
YusufEmad04
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Value vs Reference Types in Swift using Wikipedia implementation of Heap's permutation algorithm as example

I was trying to write code for determining permutations. In Wikipedia there is psuedo code for a simple algorithm (from BR Heap). I attempted to translate the psuedo code procedure generate(k : integer, A : array of any): if k = 1 then …
Bibbs1000
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