The repository is a collection of open-source implementation of a variety of algorithms implemented in Go and licensed under MIT License.
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ahocorasick
Advanced
: Advanced Function performing the Advanced Aho-Corasick algorithm. Finds and prints occurrences of each pattern.AhoCorasick
: AhoCorasick Function performing the Basic Aho-Corasick algorithm. Finds and prints occurrences of each pattern.ArrayUnion
: ArrayUnion Concats two arrays of int's into one.BoolArrayCapUp
: BoolArrayCapUp Dynamically increases an array size of bool's by 1.BuildAc
: Functions that builds Aho Corasick automaton.BuildExtendedAc
: BuildExtendedAc Functions that builds extended Aho Corasick automaton.ComputeAlphabet
: ComputeAlphabet Function that returns string of all the possible characters in given patterns.ConstructTrie
: ConstructTrie Function that constructs Trie as an automaton for a set of reversed & trimmed strings.Contains
: Contains Returns 'true' if array of int's 's' contains int 'e', 'false' otherwise.CreateNewState
: CreateNewState Automaton function for creating a new state 'state'.CreateTransition
: CreateTransition Creates a transition for function σ(state,letter) = end.GetParent
: GetParent Function that finds the first previous state of a state and returns it. Used for trie where there is only one parent.GetTransition
: GetTransition Returns ending state for transition σ(fromState,overChar), '-1' if there is none.GetWord
: GetWord Function that returns word found in text 't' at position range 'begin' to 'end'.IntArrayCapUp
: IntArrayCapUp Dynamically increases an array size of int's by 1.StateExists
: StateExists Checks if state 'state' exists. Returns 'true' if it does, 'false' otherwise.
Result
: No description provided.
avl
Package avl is a Adelson-Velskii and Landis tree implemnation avl is self-balancing tree, i.e for all node in a tree, height difference between its left and right child will not exceed 1 more information : https://en.wikipedia.org/wiki/AVL_tree
Delete
: Delete : remove given key from the treeGet
: Get : return node with given keyInsert
: Insert a new itemNewTree
: NewTree create a new AVL tree
Node
: No description provided.
binary
BitCounter
: BitCounter - The function returns the number of set bits for an unsigned integer numberIsPowerOfTwo
: IsPowerOfTwo This function uses the fact that powers of 2 are represented like 10...0 in binary, and numbers one less than the power of 2 are represented like 11...1. Therefore, using the and function: 10...0 & 01...1 00...0 -> 0 This is also true for 0, which is not a power of 2, for which we have to add and extra condition.IsPowerOfTwoLeftShift
: IsPowerOfTwoLeftShift This function takes advantage of the fact that left shifting a number by 1 is equivalent to multiplying by 2. For example, binary 00000001 when shifted by 3 becomes 00001000, which in decimal system is 8 or = 2 * 2 * 2MeanUsingAndXor
: MeanUsingAndXor This function finds arithmetic mean using "AND" and "XOR" operationsMeanUsingRightShift
: MeanUsingRightShift This function finds arithmetic mean using right shiftReverseBits
: ReverseBits This function initialized the result by 0 (all bits 0) and process the given number starting from its least significant bit. If the current bit is 1, set the corresponding most significant bit in the result and finally move on to the next bit in the input number. Repeat this till all its bits are processed.XorSearchMissingNumber
: XorSearchMissingNumber This function finds a missing number in a sequence
binarytree
AccessNodesByLayer
: AccessNodesByLayer Function that access nodes layer by layer instead of printing the results as one line.BstDelete
: BstDelete removes the nodeInOrder
: Travers the tree in the following order left --> root --> rightInOrderSuccessor
: InOrderSuccessor Goes to the leftInsert
: Insert a value in the BSTreeLevelOrder
: No description provided.Max
: Max Function that returns max of two numbers - possibly already declared.NewNode
: NewNode Returns a new pointer to an empty NodePostOrder
: Travers the tree in the following order left --> right --> rootPreOrder
: Travers the tree in the following order root --> left --> right
caesar
Package caesar is the shift cipher ref: https://en.wikipedia.org/wiki/Caesar_cipher
Decrypt
: Decrypt decrypts by left shift of "key" each character of "input"Encrypt
: Encrypt encrypts by right shift of "key" each character of "input"
coloring
Package coloring provides implementation of different graph coloring algorithms, e.g. coloring using BFS, using Backtracking, using greedy approach. Author(s): Shivam
BipartiteCheck
: basically tries to color the graph in two colors if each edge connects 2 differently colored nodes the graph can be considered bipartite
Graph
: No description provided.
conversion
Base64Decode
: Base64Decode decodes the received input base64 string into a byte slice. The implementation follows the RFC4648 standard, which is documented at https://datatracker.ietf.org/doc/html/rfc4648#section-4Base64Encode
: Base64Encode encodes the received input bytes slice into a base64 string. The implementation follows the RFC4648 standard, which is documented at https://datatracker.ietf.org/doc/html/rfc4648#section-4BinaryToDecimal
: BinaryToDecimal() function that will take Binary number as string, and return it's Decimal equivalent as integer.DecimalToBinary
: DecimalToBinary() function that will take Decimal number as int, and return it's Binary equivalent as string.HEXToRGB
: HEXToRGB splits an RGB input (e.g. a color in hex format; 0x) into the individual components: red, green and blueIntToRoman
: IntToRoman converts an integer value to a roman numeral string. An error is returned if the integer is not between 1 and 3999.RGBToHEX
: RGBToHEX does exactly the opposite of HEXToRGB: it combines the three components red, green and blue to an RGB value, which can be converted to e.g. HexReverse
: Reverse() function that will take string, and returns the reverse of that string.RomanToInteger
: RomanToInteger converts a roman numeral string to an integer. Roman numerals for numbers outside the range 1 to 3,999 will return an error. Nil or empty string return 0 with no error thrown.
diffiehellman
Package diffiehellman implements Deffie Hellman Key Exchange Algorithm for more information watch : https://www.youtube.com/watch?v=NmM9HA2MQGI
GenerateMutualKey
: GenerateMutualKey : generates a mutual key that can be used by only alice and bob mutualKey = (shareKey^prvKey)%primeNumberGenerateShareKey
: GenerateShareKey : generates a key using client private key , generator and primeNumber this key can be made public shareKey = (g^key)%primeNumber
dynamic
Bin2
: Bin2 functionCutRodDp
: CutRodDp solve the same problem using dynamic programmingCutRodRec
: CutRodRec solve the problem recursively: initial approachEditDistanceDP
: EditDistanceDP is an optimised implementation which builds on the ideas of the recursive implementation. We use dynamic programming to compute the DP table where dp[i][j] denotes the edit distance value of first[0..i-1] and second[0..j-1]. Time complexity is O(m * n) where m and n are lengths of the strings, first and second respectively.EditDistanceRecursive
: EditDistanceRecursive is a naive implementation with exponential time complexity.IsSubsetSum
: No description provided.Knapsack
: Knapsack solves knapsack problem return maxProfitLongestCommonSubsequence
: LongestCommonSubsequence functionLongestIncreasingSubsequence
: LongestIncreasingSubsequence returns the longest increasing subsequence where all elements of the subsequence are sorted in increasing orderLpsDp
: LpsDp functionLpsRec
: LpsRec functionMatrixChainDp
: MatrixChainDp functionMatrixChainRec
: MatrixChainRec functionMax
: Max function - possible duplicateNthCatalanNumber
: NthCatalan returns the n-th Catalan Number Complexity: O(n²)NthFibonacci
: NthFibonacci returns the nth Fibonacci Number
dynamicarray
Package dynamicarray A dynamic array is quite similar to a regular array, but its Size is modifiable during program runtime, very similar to how a slice in Go works. The implementation is for educational purposes and explains how one might go about implementing their own version of slices. For more details check out those links below here: GeeksForGeeks article : https://www.geeksforgeeks.org/how-do-dynamic-arrays-work/ Go blog: https://blog.golang.org/slices-intro Go blog: https://blog.golang.org/slices authors Wesllhey Holanda, Milad see dynamicarray.go, dynamicarray_test.go
DynamicArray
: No description provided.
factorial
Iterative
: Iterative returns the iteratively brute forced factorial of nRecursive
: Recursive This function recursively computes the factorial of a numberUsingTree
: UsingTree This function finds the factorial of a number using a binary tree
fibonacci
gcd
Extended
: Extended simple extended gcdExtendedIterative
: ExtendedIterative finds and returns gcd(a, b), x, y satisfying ax + by = gcd(a, b).ExtendedRecursive
: ExtendedRecursive finds and returns gcd(a, b), x, y satisfying ax + by = gcd(a, b).Iterative
: Iterative Faster iterative version of GcdRecursive without holding up too much of the stackRecursive
: Recursive finds and returns the greatest common divisor of a given integer.TemplateBenchmarkExtendedGCD
: No description provided.TemplateBenchmarkGCD
: No description provided.TemplateTestExtendedGCD
: No description provided.TemplateTestGCD
: No description provided.
genetic
Package genetic provides functions to work with strings using genetic algorithm. https://en.wikipedia.org/wiki/Genetic_algorithm Author: D4rkia
GeneticString
: GeneticString generates PopultaionItem based on the imputed target string, and a set of possible runes to build a string with. In order to optimise string generation additional configurations can be provided with Conf instance. Empty instance of Conf (&Conf{}) can be provided, then default values would be set. Link to the same algorithm implemented in python: https://github.com/TheAlgorithms/Python/blob/master/genetic_algorithm/basic_string.py
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Conf
: No description provided. -
PopulationItem
: No description provided. -
Result
: No description provided.
geometry
Distance
: Calculates the shortest distance between two points.Intercept
: Calculates the Y-Intercept of a line from a specific Point.IsParallel
: Checks if two lines are parallel or not.IsPerpendicular
: Checks if two lines are perpendicular or not.PointDistance
: Calculates the distance of a given Point from a given line. The slice should contain the coefficiet of x, the coefficient of y and the constant in the respective order.Section
: Calculates the Point that divides a line in specific ratio. DO NOT specify the ratio in the form m:n, specify it as r, where r = m / n.Slope
: Calculates the slope (gradient) of a line.
graph
Package graph demonstrates Graph search algorithms reference: https://en.wikipedia.org/wiki/Tree_traversal
BreadthFirstSearch
: BreadthFirstSearch is an algorithm for traversing and searching graph data structures. It starts at an arbitrary node of a graph, and explores all of the neighbor nodes at the present depth prior to moving on to the nodes at the next depth level. Worst-case performance O(|V|+|E|)=O(b^{d})}O(|V|+|E|)=O(b^{d}) Worst-case space complexity O(|V|)=O(b^{d})}O(|V|)=O(b^{d}) reference: https://en.wikipedia.org/wiki/Breadth-first_searchDepthFirstSearch
: No description provided.DepthFirstSearchHelper
: No description provided.FloydWarshall
: FloydWarshall Returns all pair's shortest path using Floyd Warshall algorithmGetIdx
: No description provided.KruskalMST
: KruskalMST will return a minimum spanning tree along with its total cost to using Kruskal's algorithm. Time complexity is O(m * log (n)) where m is the number of edges in the graph and n is number of nodes in it.New
: Constructor functions for graphs (undirected by default)NewDSU
: NewDSU will return an initialised DSU using the value of n which will be treated as the number of elements out of which the DSU is being madeNotExist
: No description provided.Topological
: Assumes that graph given is valid and possible to get a topo ordering. constraints are array of []int{a, b}, representing an edge going from a to b
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DisjointSetUnion
: No description provided. -
DisjointSetUnionElement
: No description provided. -
Edge
: No description provided. -
Graph
: No description provided. -
Item
: No description provided. -
WeightedGraph
: No description provided.
hashmap
Make
: Make creates a new HashMap instance with input size and capacityNew
: New return new HashMap instance
HashMap
: No description provided.
kmp
Kmp
: Kmp Function kmp performing the Knuth-Morris-Pratt algorithm. Prints whether the word/pattern was found and on what position in the text or not. m - current match in text, i - current character in w, c - amount of comparisons.
Result
: No description provided.
linkedlist
JosephusProblem
: https://en.wikipedia.org/wiki/Josephus_problem This is a struct-based solution for Josephus problem.NewCyclic
: Create new list.NewDoubly
: No description provided.NewNode
: Create new node.NewSingly
: NewSingly returns a new instance of a linked list
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Cyclic
: No description provided. -
Doubly
: No description provided. -
Node
: No description provided. -
Singly
: No description provided. -
testCase
: No description provided.
math
IsPowOfTwoUseLog
: IsPowOfTwoUseLog This function checks if a number is a power of two using the logarithm. The limiting degree can be from 0 to 63. See alternatives in the binary package.Phi
: Phi is the Euler totient function. This function computes the number of numbers less then n that are coprime with n.
max
Bitwise
: Bitwise computes using bitwise operator the maximum of all the integer input and returns itInt
: Int is a function which returns the maximum of all the integers provided as arguments.
maxsubarraysum
Package maxsubarraysum is a package containing a solution to a common problem of finding max contiguous sum within a array of ints.
MaxSubarraySum
: MaxSubarraySum returns the maximum subarray sum
min
Bitwise
: Bitwise This function returns the minimum integer using bit operationsInt
: Int is a function which returns the minimum of all the integers provided as arguments.
modular
Exponentiation
: Exponentiation returns base^exponent % modInverse
: Inverse Modular functionMultiply64BitInt
: Multiply64BitInt Checking if the integer multiplication overflows
nested
IsBalanced
: IsBalanced returns true if provided input string is properly nested. Input is a sequence of brackets: '(', ')', '[', ']', '{', '}'. A sequence of bracketss
is considered properly nested if any of the following conditions are true: -s
is empty; -s
has the form (U) or [U] or {U} where U is a properly nested string; -s
has the form VW where V and W are properly nested strings. For example, the string "()()[()]" is properly nested but "[(()]" is not. Note Providing characters other then brackets would return false, despite brackets sequence in the string. Make sure to filter input before usage.
permutation
GenerateElementSet
: No description provided.Heaps
: Heap's Algorithm for generating all permutations of n objects
pi
spigotpi_test.go description: Test for Spigot Algorithm for the Digits of Pi author(s) red_byte see spigotpi.go
MonteCarloPi
: No description provided.Spigot
: No description provided.
polybius
Package polybius is encrypting method with polybius square ref: https://en.wikipedia.org/wiki/Polybius_square#Hybrid_Polybius_Playfair_Cipher
NewPolybius
: NewPolybius returns a pointer to object of Polybius. If the size of "chars" is longer than "size", "chars" are truncated to "size".
Polybius
: No description provided.
power
IterativePower
: IterativePower is iterative O(logn) function for pow(x, y)RecursivePower
: RecursivePower is recursive O(logn) function for pow(x, y)RecursivePower1
: RecursivePower1 is recursive O(n) function for pow(x, y)UsingLog
: No description provided.
prime
Factorize
: Factorize is a function that computes the exponents of each prime in the prime factorization of nGenerate
: Generate returns a int slice of prime numbers up to the limitGenerateChannel
: Generate generates the sequence of integers starting at 2 and sends it to the channelch
MillerRabinTest
: MillerRabinTest Probabilistic test for primality of an integer based of the algorithm devised by Miller and Rabin.MillerTest
: MillerTest This is the intermediate step that repeats within the miller rabin primality test for better probabilitic chances of receiving the correct result.NaiveApproach
: NaiveApproach checks if an integer is prime or not. Returns a bool.PairApproach
: PairApproach checks primality of an integer and returns a bool. More efficient than the naive approach as number of iterations are less.Sieve
: Sieve Sieving the numbers that are not prime from the channel - basically removing them from the channels
pythagoras
Distance
: Distance calculates the distance between to vectors with the Pythagoras theorem
Vector
: No description provided.
queue
BackQueue
: BackQueue return the Back valueDeQueue
: DeQueue it will be removed the first value that added into the listEnQueue
: EnQueue it will be added new value into our listFrontQueue
: FrontQueue return the Front valueIsEmptyQueue
: IsEmptyQueue check our list is empty or notLenQueue
: LenQueue will return the length of the queue list
rsa
Decrypt
: Decrypt decrypts encrypted rune slice based on the RSA algorithmEncrypt
: Encrypt encrypts based on the RSA algorithm - uses modular exponentitation in math directory
search
BoyerMoore
: Implementation of boyer moore string search O(l) where l=len(text)Naive
: Implementation of naive string search O(n*m) where n=len(txt) and m=len(pattern)
set
package set implements a Set using a golang map. This implies that only the types that are accepted as valid map keys can be used as set elements. For instance, do not try to Add a slice, or the program will panic.
New
: New gives new set.
sha256
Hash
: Hash hashes the input message using the sha256 hashing function, and return a 32 byte array. The implementation follows the RGC6234 standard, which is documented at https://datatracker.ietf.org/doc/html/rfc6234
sort
Comb
: No description provided.Count
: No description provided.Exchange
: No description provided.HeapSort
: No description provided.ImprovedSimpleSort
: ImprovedSimpleSort is a improve SimpleSort by skipping an unnecessary comparison of the first and last. This improved version is more similar to implementation of insertion sortInsertionSort
: No description provided.Mergesort
: Mergesort Perform mergesort on a slice of intsPigeonhole
: Pigeonhole sorts a slice using pigeonhole sorting algorithm.QuickSort
: QuickSort Sorts the entire arrayQuickSortRange
: QuickSortRange Sorts the specified range within the arrayRadixSort
: No description provided.SelectionSort
: No description provided.ShellSort
: No description provided.SimpleSort
: No description provided.
stack
transposition
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KeyMissingError
: No description provided. -
NoTextToEncryptError
: No description provided.
trie
Package trie provides Trie data structures in golang. Wikipedia: https://en.wikipedia.org/wiki/Trie
NewNode
: NewNode creates a new Trie node with initialized children map.
Node
: No description provided.
xor
Package xor is an encryption algorithm that operates the exclusive disjunction(XOR) ref: https://en.wikipedia.org/wiki/XOR_cipher
Decrypt
: Decrypt decrypts with Xor encryptionEncrypt
: Encrypt encrypts with Xor encryption after converting each character to byte The returned value might not be readable because there is no guarantee which is within the ASCII range If using other type such as string, []int, or some other types, add the statements for converting the type to []byte.