"No code library is complete without a binary search!"
A library and repository of algorithms, data structures and helper methods that make one's daily programming life easier (in .NET that is).
Abacaxi is available on NuGet: https://www.nuget.org/packages/Abacaxi/ and is built against .NET Standard 2.0 and .NET 4.5.
F# bindings are available in the Abacaxi.FSharp library (targets .NET Standard 2.0 only).
Note that not all C# methods have F# bindings since F# core library already contains comparable implementations. Also, some methods in F# do not make sense in C# world as well.
| Data structure | Description |
|---|---|
Heap |
Implements the heap data structure (also known as priority queue). Related material: https://en.wikipedia.org/wiki/Heap_(data_structure) |
MeanHeap |
Helper class that uses two heaps to provide O(1) mean value access to a sequence. Related material: https://en.wikipedia.org/wiki/Heap_(data_structure) |
BitSet |
Implements the standard ISet<int> data structure in an optimized form (using bit masks). Related material: https://en.wikipedia.org/wiki/Bit_array |
DisjointSet |
Also known as union-find or merge-find data structure. Related material: https://en.wikipedia.org/wiki/Disjoint-set_data_structure |
LinkedLinkedNode |
Represents a node in a singly-linked list. All operations implemented by the node classes. Related material: https://en.wikipedia.org/wiki/Linked_list |
Trie |
A trie that implements the IDictionary<TKey, TValue> interface. Related material: https://en.wikipedia.org/wiki/Trie |
AvlTree |
The standard AVL self-balancing tree. Related material: https://en.wikipedia.org/wiki/AVL_tree |
BinarySearchTree |
The standard binary search tree. Related material: https://en.wikipedia.org/wiki/Binary_search_tree |
LeftLeaningRedBlackTree |
The simplified version of Red/Black self-balancing tree. Related material: https://en.wikipedia.org/wiki/Left-leaning_red%E2%80%93black_tree |
Graph |
A generic (un)directional weighted graph that implements many algorithms. Related material: https://en.wikipedia.org/wiki/Graph |
ChessHorsePathGraph |
A specialized graph implementation used to solve the Knight's Tour problem. Related material: https://en.wikipedia.org/wiki/Knight%27s_tour |
StringNeighborhoodGraph |
A specialized graph implementation used to solve the Word Ladder problem. Related material: https://en.wikipedia.org/wiki/Word_ladder |
MazeGraph |
A specialized base class for other graphs that use a two-dimensional integer board (think, a rat's maze). All standard graph algorithms can be applied to such a graph. |
LiteralGraph |
A specialized graph used mainly in testing the graph-related algorithms. |
Mash |
The Swiss army knife of collections. In essence, a tree-like dictionary which can have other sub-dictionaries as children and store a list of items as leaves. Employs some techniques to avoid wasting unnecessary memory. |
| Class | Description |
|---|---|
ArrayEqualityComparer |
Implements an equality comparer that is able to check two array for equality. The class is useful when using dictionaries/sets whose keys are arrays. |
Temporary |
A class used to store a value for a specific amount of time. The value expires and has to be reloaded. Multi-threaded |
BitWriter |
A specialized I/O class that implements the Stream base class. Allows for writing to a stream with bit granularity. |
GlobPattern |
Simple class that allows checking if a string matches a glob-like pattern (e.g. "some*.?xt") |
DependencySquid |
Class that helps represent the state of a dependancy tree (including conflicts). Can be used to validate selection viability (think package dependancies). |
Cached |
A simple wrapper that allows storing a value and considering it "valid" for a certain duration. Automatic value refresh is performed when value expires. |
NanoCache |
A very simple cache container. Very useful when quick-and-dirty caching is needed. |
| Algorithm/Method | Description |
|---|---|
LinkedListNode.TryGetMiddleAndTailNodes |
Finds the middlem, tail nodes and the length of the list in one pass. If the list is circular, the method returns -1 See related material: https://en.wikibooks.org/wiki/Data_Structures/LinkedLists |
LinkedListNode.Reverse |
Reverses a singly-linked list using the recursive algorithm. See related material: https://en.wikibooks.org/wiki/Data_Structures/LinkedLists |
LinkedListNode.GetIntersectionNode |
Find the node that is the intersection of two singly-linked. See related material: https://en.wikibooks.org/wiki/Data_Structures/LinkedLists |
LinkedListNode.GetKnotNode |
Find the node that connects the tail of the list to another interior node (knot) in a singly-linked. See related material: https://www.geeksforgeeks.org/detect-and-remove-loop-in-a-linked-list/ |
Graph.TraverseBfs |
Traverses the vertices in a graph using the breadth-first search. See related material: https://en.wikipedia.org/wiki/Breadth-first_search |
Graph.TraverseDfs |
Traverses the vertices in a graph using the depth-first search. See related material: https://en.wikipedia.org/wiki/Depth-first_search |
Graph.FillWithOneColor |
Fills all vertices of a graph with a given "color". See related material: https://en.wikipedia.org/wiki/Flood_fill |
Graph.FindShortestPath |
Find the shortest path between two graph vertices. See related material: https://en.wikipedia.org/wiki/Shortest_path_problem |
Graph.GetComponents |
Finds all distinct connected components of a graph. The method returns each component represented as another graph. See related material: https://en.wikipedia.org/wiki/Connected_component_(graph_theory) |
Graph.TopologicalSort |
Implements the topological sorting algorithm. See related material: https://en.wikipedia.org/wiki/Topological_sorting |
Graph.FindAllArticulationVertices |
Finds all articulation points in a graph. See related material: https://en.wikipedia.org/wiki/Biconnected_component |
Graph.IsBipartite |
Checks if a graph is bipartite. See related material: https://en.wikipedia.org/wiki/Bipartite_graph |
Graph.DescribeVertices |
Returns a description of all vertices in a graph, including in-degree, out-degree and component index. |
Graph.FindCheapestPath |
Finds the cheapest path between two vertices in a graph. See related material: https://en.wikipedia.org/wiki/A*_search_algorithm |
Graph.Colorize |
Finds the minimum number of colors and applies thm on graph verticesh. See related material: https://en.wikipedia.org/wiki/Graph_coloring |
FibonacciSequence.Enumerate |
Lists all Fibonacci numbers up to a given index in the series. See related material: https://en.wikipedia.org/wiki/Fibonacci_number |
FibonacciSequence.GetMember |
Returns the Fibonacci number at a given index in the series. See related material: https://en.wikipedia.org/wiki/Fibonacci_number |
Integer.DeconstructIntoPowersOfTwo |
Deconstructs an integer into a sum of powers of two. |
Integer.DeconstructIntoPrimeFactors |
Deconstructs an integer into a prime factors. |
Integer.Break |
Deconstructs an integer into repeatable components. See related material: https://en.wikipedia.org/wiki/Change-making_problem |
Integer.IsPrime |
Checks whether an integer is a prime number. |
Integer.Zip |
Zips the digits of two integers into a new integer. |
Integer.Divide |
A simple division algorithm that only uses addition. |
Integer.Swap |
Algorithm that performs a swap of two integers without an additional variable. |
Integer. GetCountOfTrailingZeroesInFactorial |
Find the number of trailing zeroes for a factorial number. See related material: https://www.geeksforgeeks.org/count-trailing-zeroes-factorial-number/ |
Integer.Max |
Returns the maximum of two integers without using comparisons. |
Integer.Sum |
Returns the sum of two integers using only bitwise operations. |
IntegerPartitions.Enumerate |
Enumerates all integer partitions for a given number. |
IntegerPartitions.GetCount |
Calculates the number of integer partitions for a given number. |
Knapsack.Fill |
The generic 0/1 knapsack algorithm. See related material: https://en.wikipedia.org/wiki/Knapsack_problem |
Interval.MergeOverlapping |
Merges a sequence of overlapping intervals (or whatever intervals do overlap) leaving the other ones untouched. |
Interval.ChoseBestNonOverlapping |
Selects the non-overlapping (and scored) intervals that yeild the best aggregate score. |
Pairing.GetPairsWithMinimumCost |
Pairs the elements of a sequence as to minimize the cost of each pair. |
Pairing. GetPairsWithApproximateMinimumCost |
Pairs the elements of a sequence as to approximate minimization of the cost of each pair. |
Pairing.GetPairWithMaximumDifference |
Find the first pair in a sequence whose elements yield the greatest difference. |
Pairing. GetPairWithIncreasingOrderMaximumDifference |
Find the first pair in a sequence whose elements yield the greatest difference with the restriction that elements in eth pair are strictly increasing. |
Pairing.GetEqualizationPairs |
Finds all pairs of elements from both sequences whose values, if swapped, makes the sequences being equal in their sum. |
ZArray.Construct |
Constructs a Z-array from a given input sequence. Z-arrays are useful for string pattern matching. See related materials: http://wittawat.com/assets/talks/z_algorithm.pdf, https://shiv4289.wordpress.com/2013/09/17/z-algorithm-for-pattern-matching/ |
RandomExtensions.Sample |
A random sampling algorithm for a sequence of objects. See related material: https://en.wikipedia.org/wiki/Reservoir_sampling |
RandomExtensions.NextBool |
An extension method that allows retrieving a random boolean value. |
RandomExtensions.NextItem |
An extension method that allows retrieving a random item from a sequence of objects. |
SequenceAlgorithms. FindLongestIncreasingSequence |
Finds the longest increasing sequence within a given sequence. |
SequenceAlgorithms. ContainsTwoElementsThatAggregateTo |
Determines whether the sequence contains two elements that aggregate to a given target. |
SequenceAlgorithms.FindDuplicates |
Finds duplicates in a sequence. A specialized and optimized version for integer sequences also provided. |
SequenceAlgorithms.FindUniques |
Finds unique elements in a sequence. |
SequenceAlgorithms.FindUniquesInOrder |
Finds unique elements in a sequence and retains the order of their appearance in the sequence. |
SequenceAlgorithms.ExtractNestedBlocks |
An algorithm to allow extracting nested sub-sequences from a sequence (e.g. "(a(b))" would return "(b)" then "(a(b))"). |
SequenceAlgorithms. GetSubsequencesOfAggregateValue |
Finds all sub-sequences of a given aggregated value in another sequence. |
SequenceAlgorithms.Interleave |
Creates a sequence which combines multiple interleaved sequences based on a given comparison. |
SequenceAlgorithms.Reverse |
Reverses a sequence in place. |
SequenceAlgorithms.Repeat |
Creates a sequence which is based on the original sequence repeated a number of times. |
SequenceAlgorithms.BinarySearch |
Implements the standard binary search algorithm. See related material: https://en.wikipedia.org/wiki/Binary_search_algorithm |
SequenceAlgorithms.BinaryLookup |
Implements a slightly modified binary search algorithm that returns the range of matching items or the position of immediatelly smaller item. See related material: https://en.wikipedia.org/wiki/Binary_search_algorithm |
SequenceAlgorithms.Diff |
Implements the generic edit distance algorithm. See related material: https://en.wikipedia.org/wiki/Edit_distance |
SequenceAlgorithms. GetLongestCommonSubSequence |
Finds the longest sub-sequence that is common to two distinct sequences. See related material: https://en.wikipedia.org/wiki/Longest_common_subsequence_problem |
SequenceAlgorithms.DeconstructIntoTerms |
Deconstructs a given sequence into a sequence of terms (sub-sequences) based on given term scoring (e.g. think of recognizing an English phrase for all lower-case text without whitespaces using a given dictionary of known words: "ilovecookies" will be split into "i", "love", "cookies"). |
SequenceAlgorithms.GetItemFrequencies |
Gets the items and their frequencies within a sequence. |
SequenceAlgorithms.IsPalindrome |
Checks if a given (sub)sequence is a palindrome. See related material: https://en.wikipedia.org/wiki/Palindrome |
SequenceAlgorithms. IsPermutationOfPalindrome |
Checks if a given (sub)sequence is a possible permutation of palindrome. See related material: https://en.wikipedia.org/wiki/Palindrome |
SequenceAlgorithms.IndexOfPermutationOf |
Finds the first occurence of sub-sequence (or any of its permutations) in the given sequence. |
SequenceAlgorithms. FindUnorderedSubsequenceRange |
Finds the un-ordered sub-sequence inside a given sequence. Once found sub-sequence is sorted, the whole sequence becomes ordered. |
SequenceAlgorithms. GetRangeWithGreatestAggregateValue |
Finds the sub-sequence range with the greatest aggregate value. |
SequenceExtensions.ToSet |
Helper methods to convert a given sequence into a set. |
SequenceExtensions.AsList |
Helper method that interprets a given sequence as a list. If the sequence is already a list/array then the original object is returned; otherwise, the sequence is converted to an array. This method may or may not create a new object and does not guarantee mutability of the result. |
SequenceExtensions.Copy |
Helper method to copy a sub-sequence into a new array. |
SequenceExtensions.AddOrUpdate |
Extends the dictionary classes with the ability to add a new, or update an existing key/pair. |
SequenceExtensions.Increment |
Extends the dictionary classes with the ability to increment integer value for a given key (treating non-existing keys as having value of zero). |
SequenceExtensions.Append |
A number of small utility methods used to append items to arrays. If the array is null, a new array is created. These methods return new arrays as their return values. |
SequenceExtensions.ToList |
Utility method that replaces a common "Select(...).Tolist()" LINQ pattern. |
SequenceExtensions.Partition |
Partitions a given sequence into a batch of smaller partitions of a given size. |
SequenceExtensions.EmptyIfNull |
Method returns an empty sequence if the current sequence is null; otherwise it returns the sequence itself. |
SequenceExtensions.IsNullOrEmpty |
Mimics the String.IsNullOrEmpty method. |
SequenceExtensions.ToString |
Utility method that replaces a common "String.Join(..., ...Select(...))" LINQ pattern. |
SequenceExtensions.Min |
Returns the element of a sequence with a given selected minimum (e.g. select the person object with the smallest age). |
SequenceExtensions.Max |
Returns the element of a sequence with a given selected maximum (e.g. select the person object with the greatest age). |
SequenceExtensions.Segment |
Returns a view of the original sequence bounded to a segment of the list. Useful when other methods do not allow specifying a start/length pair of arguments. |
SequenceExtensions.SelectValues |
Selects the values of a sequence of nullables. Nullable items that have no value are skipped. |
SequenceExtensions.Separate |
Separates items from a sequence into two distinct arrays based on a predicate. |
SequenceExtensions.Unzip |
Splits tuples (and key-value pairs) into separate array containing individual items. |
SequenceExtensions.IsValidAdjacency |
Checkes whether all sequence adjacent elements satisfy a common condition. |
SequenceExtensions.IsOrdered |
Checkes whether the elements of a given sequence are sorted in ascending order. |
SequenceExtensions.IsStrictlyOrdered |
Checkes whether the elements of a given sequence are strictly sorted in ascending order. |
SequenceExtensions.IsOrderedDescending |
Checkes whether the elements of a given sequence are sorted in descending order. |
SequenceExtensions. IsStrictlyOrderedDescending |
Checkes whether the elements of a given sequence are strictly sorted in descending order. |
SequenceExtensions.Fold |
Folds a sequence by merging consecutive appearances of a given item into one output item (think reduce). |
Set.EnumerateSubsetCombinations |
Splits a set into subsets of a given length and returns all such combinations. |
Set.SplitIntoSubsetsOfEqualValue |
Tries to find all subsets with equal aggregate value. See related material: http://www.usaco.org/index.php?page=viewproblem2&cpid=139 |
Set.GetSubsetWithNearValue |
Extracts a subset of integers whose sum is equal or very close to the target value. |
Set.ContainsSubsetWithExactValue |
Checks whether there is a subset of integers whose sum is equal to a target value. |
Set.GetSubsetWithGreatestValue |
Finds the first N number of pairs with greatest sums. |
Set.GetPermutations |
Evaluates and returns all permutations of a given set. See related material: https://en.wikipedia.org/wiki/Permutation |
Sorting.BubbleSort |
Implements the standard bubble sort algorithm. See related material: https://en.wikipedia.org/wiki/Bubble_sort |
Sorting.CocktailShakerSort |
Implements the standard cocktail shaker sort algorithm. See related material: https://en.wikipedia.org/wiki/Cocktail_shaker_sort |
Sorting.CombSort |
Implements the standard comb sort algorithm. See related material: https://en.wikipedia.org/wiki/Comb_sort |
Sorting.GnomeSort |
Implements the standard gnome sort algorithm. See related material: https://en.wikipedia.org/wiki/Gnome_sort |
Sorting.HeapSort |
Implements the standard heapsort algorithm. See related material: https://en.wikipedia.org/wiki/Heapsort |
Sorting.InsertionSort |
Implements the standard insertion sort algorithm. See related material: https://en.wikipedia.org/wiki/Insertion_sort |
Sorting.MergeSort |
Implements the standard merge sort algorithm. See related material: https://en.wikipedia.org/wiki/Merge_sort |
Sorting.OddEvenSort |
Implements the standard odd-even sort algorithm. See related material: https://en.wikipedia.org/wiki/Odd%E2%80%93even_sort |
Sorting.QuickSort |
Implements the standard quicksort algorithm. See related material: https://en.wikipedia.org/wiki/Quicksort |
Sorting.ShellSort |
Implements the standard shellsort algorithm. See related material: https://en.wikipedia.org/wiki/Shellsort |
ObjectExtensions.IsAnyOf |
Helper methods that allows checking if an object is equal to any other object in a sequence (think of _x IN (o1, o2, o3)). |
ObjectExtensions.Inspect |
A simple helper method that allows extracting fields/properties/methods values from an object as a dictionary. |
ObjectExtensions.TryConvert |
Tries to convert a given object to a given type. Uses different techniques to achieve this goal. |
ObjectExtensions.As |
A simpler version of TryConvert that throws an exception if the conversion is not possible. |
StringExtensions.AsList |
Returns a wrapper IList<char> object. Useful when using other algorithms that expect a list. The returned list is read-only for obvious reasons. |
StringExtensions.Reverse |
Reverses a string and returns the reversed version. |
StringExtensions.Shorten |
Shortens a string to a given maximum length (considering Unicode surrogate-pairs, etc.). Allows for an optional "shortening indicator string" used at the end of the string (think "This is a go..."). |
StringExtensions.Escape |
Escapes a string using the standard "C" escape sequences (e.g. "\n" for new line). |
StringExtensions.Like |
A wrapper method on top of GlobPattern class. A convenient method to check if a string matches a pattern. |
StringExtensions.FindDuplicates |
Finds duplicate characters in the string. Uses both a set and a small array for ASCII characters. |
StringExtensions.SplitIntoLines |
Splits a given string into its contituent lines. Treats both "\n" and "\r\n" as line breaks. |
StringExtensions.WordWrap |
Word-wraps a string to a given max line length. Uses white-spaces and puctuation characters as potential line breaks. |
StringExtensions.StripDiacritics |
Strips the Unicode diacritics from a text. Useful for text normalization in searches. |
StringBuilderExtensions. AppendNotEmptyLine |
Appends a line to the string builder if the line is not empty. |