This is the web page of terms with definitions that have links to implementations with source code. The language is in parentheses. We also list all entries by type, for instance, whether it is an algorithm, a definition, a problem, or a data structure, and entries by area, for instance, graphs, trees, sorting, etc.

Don't use this site to cheat. Teachers, contact us if we can help.

We need people to contribute. If you have suggestions, corrections, or comments, please get in touch with Paul Black. You are welcome to make suggestions to expand and improve the DADS.

By selecting almost any of these links, you will be leaving the DADS webspace. We provided these links because they may have information of interest to you. No inferences should be drawn because some sites are referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. We do not necessarily endorse the views expressed, or concur with the facts presented on these sites.

A great source of implementations, organized by area and reviewed for quality, is the Stony Brook Algorithm Repository. A great source of implementations of mathematical functions is the NIST Guide to Available Mathematical Software or GAMS.

Java is a trademark of Sun Microsystems, Inc.

Run on Fri Oct 25 17:11:48 2024

• Ackermann's function: History of the function and (Modula-2) code.
• adjacency-list representation: Sedgewick and Wayne "Algorithms" 4th edition's implementation (Java).
• adjacency-matrix representation: Algorithms and Data Structures' implementation (Java and C++). Sedgewick and Wayne "Algorithms" 4th edition's implementation (Java).
• Aho-Corasick: Bruce Watson's SPARE Parts, a string pattern recognition toolkit (C++).
• Alpha Skip Search algorithm: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• American flag sort: It is program C (C) in the McIlroy, Bostic, and McIlroy paper.
• Apostolico-Crochemore: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Apostolico-Giancarlo algorithm: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• arithmetic coding: Jürgen Abel's excellent Range and Arithmetic Coding resources (C, Java, C++), with links to papers, people, and implementations. Mark Nelson's 2014 article on Data Compression With Arithmetic Coding (C).
• array: Sedgewick & Wayne's introduction and tutorial to arrays (Java). John Morris' Data Structures - Arrays(C). Bro. David Carlson's search, access, complexity, etc. tutorial and code (C++). Hudak, Peterson, and Fasel's section on arrays (Haskell). Read and write different arrays (Fortran, C++).
• AVL tree: Ben Pfaff's explanations and code (C). Maksim Goleta's C# Collections uses it to implement sorted set (C#). Bro. David Carlson's tutorial and code (C++). Richard McGraw's Navl-latest.tar.bz2 (C#). Worst-case behavior of traversal, annotated for real time (WOOP/ADA).
• balanced binary tree: red-black tree analysis, explanation, examples, and code (C). Ben Pfaff's AVL tree explanation (C).
• balanced merge sort: (C) using an auxiliary function to select next file (C).
• BB(α) tree: Worst-case behavior of traversal, annotated for real time (WOOP/ADA), including bibliography. insert (C and Pascal) and delete (C and Pascal) that use check root (C and Pascal) (or this one or this one?), left rotation (C and Pascal), and right rotation (C and Pascal).
• Bellman-Ford algorithm: The entry in Wikipedia (C, Assembly, and pseudocode) has a proof, too.
• bidirectional bubble sort: Pat Morin's implementation, see cocktail sort (Java). (Python).
• binary heap: delete (C) and insert (C and Pascal) both of which use the auxiliary function siftup (C and Pascal), explanation, examples, and code (C). (Fortran).
• binary insertion sort: (C)
• binary priority queue: Gonnet and Baeza-Yates insert (C and Pascal) and delete (C and Pascal)
• binary search: recursive and iterative implementation (Python). search (C), which uses {0-based indexing}. Flower Brackets explanation (Java). Algorithms and Data Structures' explanation (Java and C++). Worst-case behavior annotated for real time (WOOP/ADA), including bibliography.
• binary search tree: Ben Pfaff's insert, delete, search, copy, etc. (literate C); Maksim Goleta's C# Collections uses it to implement sorted set (C#). insert (C), search (C). Algorithms and Data Structures' explanation with links to add, delete, search, and output values in order (Java and C++).
• binary tree: examples, analysis, and code (C). Bro. David Carlson's tutorial and code (C++). Worst-case behavior of traversal, annotated for real time (WOOP/ADA).
• bin packing problem: (Icon).
• bitonic sort: Prof. Dr. Hans Wener Lang's explanation, proof of correctness, analysis, bibliography, etc. (Java). (Python).
• Bloom filter: Arash Partow's implementations (C++, Object Pascal) (go to Download, at the bottom).
• bogosort: (Python).
• Boyer-Moore: Christian Charras' and Thierry Lecroq's Boyer-Moore algorithm (C). (C) which uses Boyer-Moore preprocessing (C)
• Boyer-Moore-Horspool: Christian Charras' and Thierry Lecroq's Horspool algorithm (C). Gonnet and Baeza-Yates' (C) or (Pascal)
• bozo sort: Pat Morin's implementation (Java).
• B⁺-tree: Search the web for bplus to find implementations. More targeted searches are bplustree, "b plus tree", or search the comp.sources groups for bplus.
• brute force string search: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C), (C and Pascal)
• brute force string search with mismatches: Gonnet and Baeza-Yates' (C and Pascal)
• B-tree: tutorial of how B-trees work and code (Perl), Bro. David Carlson's tutorial and code (C++). data structure definition (C and Pascal), insert (C and Pascal) using auxiliary functions (C and Pascal), search (C and Pascal), (Pick Basic) commented source code at the bottom.
• bubble sort: Algorithms and Data Structures' explanation (Java and C++). Flower Brackets (Java). (Python).
• bucket sort: analysis, explanation, and code (C), and (C).
• Burrows-Wheeler transform: Mark Nelson's great Data Compression with the Burrows-Wheeler Transform (C++) explains the algorithm. Dr. Dobb's Journal, September, 1996.
• chaining: (C)
• Chinese postman problem: (Java, C++, and Mathematica)
• clique problem: (Fortran, C, and Mathematica)
• coalesced chaining: Wikipedia article (C) (starts at the beginning of the array for empty places). insert (C) (starts at the end of the array for empty places), search (C).
• Colussi: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• comb sort: (Python).
• connected components: (C++, C, Java, and Mathematica)
• CORDIC: Wikipedia entry (C, MATLAB). dspGuru's introduction and code (C).
• counting sort: (Python).
• cube root: GAMS Class C2 has many implementations of powers, roots, and reciprocals (C and Fortran).
• cycle: Cycle detection (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• depth-first search: Algorithms and Data Structures' explanation and implementation (Java and C++) for undirected graphs. Many algorithms using depth-first search (Java) using Sedgewick and Wayne "Algorithms" 4th edition.
• deterministic finite automata string search: description and animation (C), (C) which uses a finite automaton structure (C) and builds a recognizer (C)
• dictionary: (C++, Pascal, and Fortran). Maksim Goleta's C# Collections sorted (C#) and unordered (C#).
• Dijkstra's algorithm: An analysis with code (C)
• direct chaining: insert (C), search (C). Duane A. Bailey's ChainedHashtable class documentation in the structure package (Java) from Java Structures: Data Structures in Java, for the Principled Programmer.
• directed graph: A glossary of directed graph terms and adjacency-list and -matrix, reachability, cycles, etc. implementations (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• discrete interval encoding tree: insert, delete, and member (ML), insert, delete, and member (Haskell)
• double hashing: insert (C and Pascal), search (C and Pascal)
• double metaphone: Many metaphone and double metaphone (Basic, C, Perl, and C++) implementations. Apache codec implementations of soundex, Metaphone, and Double Metaphone (Java).
• dual-pivot quicksort: Sedgewick and Wayne (Java), (C).
• dynamic programming: Mark Nelson's tutorial to using C++ Hash Table Memoization: [for] Simplifying Dynamic Programming (C++). Oleg Kiselyov's program to optimally lay out a page (C++) using dynamic programming.
• edge coloring: (C++, Mathematica, and C)
• edge connectivity: Steve Skiena's Stony Brook Algorithm Repository (C, C++, Java, and Mathematica)
• enfilade: Gold (Smalltalk).
• Euclid's algorithm: Worst-case behavior annotated for real time (WOOP/ADA).
• external quicksort: (C)
• factorial: Peter Luschny's fast factorial algorithms (Java and C#) including benchmarks and advice.
• fast fourier transform: Worst-case behavior annotated for real time (WOOP/ADA).
• feedback edge set: Steven Skiena's Stony Brook Algorithm Repository (C)
• feedback vertex set: Steven Skiena's Stony Brook Algorithm Repository (C)
• Fibonaccian search: Manolis Lourakis' fibsrch (C). Worst-case behavior annotated for real time (WOOP/ADA), including bibliography. (Interpolation and secant search "guess more precisely where the key being sought falls".)
• Fibonacci number: Find the n-th Fibonacci number with five different approaches (Python). Worst-case behavior to generate nth number, annotated for real time (WOOP/ADA).
• finite state machine: Jan Daciuk's Finite state utilities (C++) including many links to other code, papers, etc. David Lutterkort's Finite Automata library - libfa (C), which is part of Augeas, supports many operations like "compile" a regular expression into a finite automaton, minimize, union, intersect, and minus. Gertjan van Noord's Finite State Automata Utilities (Prolog), which generate C code, minimize, visualize, etc. Page has binaries, too. For regular expressions generate NFSM, make deterministic, and optimize (Haskell). Oleg Kiselyov's program to minimize a finite state machine (Prolog).
• finite state machine minimization: (C++ and Java)
• Fisher-Yates shuffle: Ben Pfaff's answer to how can I shuffle the contents of an array? (C). Mike Bostock's animations with code (JavaScript). An implementation (Java) due to Sedgewick and Wayne (search for Shuffling).
• Galil-Giancarlo: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Galil-Seiferas: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• gnome sort: (Python). (C)
• graph: GraphEd -- Graph Editor and Layout Program (C), graph manipulation (C++, C, Mathematica, and Pascal), JGraphT (Java) build, traverse, and display directed and undirected graphs. Graph generating (C, Mathematica, Pascal, C++, and Fortran), BGL - the Boost Graph Library (C++). LLX's Static Graph Template Library (LSGTL) (C). Annas (Java), for graph theory, AI, path finding, distributed systems, etc. The main libraries are Annas.Graph, graph manipulation and visualization and Annas.Math, comprehensive math functions. JUNG (Java), the Java Universal Network/Graph framework. JDSL (Java), the Data Structures Library in Java. Algorithms and Data Structures' explanation and adjacency matrix implementation (Java and C++).
• graph drawing: Draw a graph nicely (C and Mathematica), draw a graph in the plane such that no edges cross (C, C++, and Mathematica), GraphEd: Graph Editor and Layout Program (C). Graphviz: Graph Visualization Software (C), consisting of many graph drawing programs, viewers (C, Java, and TCL/TK), etc.
• graph isomorphism: (C and Mathematica)
• graph partition: (C++) explanation of problem with links to implementations. METIS is a set of programs for partitioning graphs, etc.
• greatest common divisor: Flower Brackets (Java).
• Grover's algorithm: Grover's article in Dr. Dobb's Journal, April 2001 (C-like), accessed August 2013.
• Hamiltonian cycle: (Fortran, C, Mathematica, and C++)
• hash function: See the implementations at {minimal perfect hashing} and {Pearson's hash}. Bob Jenkins' fast, parameterizable, broadly applicable hash function (C) including code for and evaluations of many other hash functions. Fowler/Noll/Vo or FNV hash function (C). Arash Partow's implementations of various General Hash Functions (C, C++, Pascal, Object Pascal, Java, Ruby, Python) and Bloom filter for strings. Gonnet and Baeza-Yates's hash functions for strings.(C). Austin Appleby's fast MurmurHash (C), including avalanche diagrams for Hsieh SuperFastHash, Jenkin's lookup3, Murmur, Bernstein, FNV, and modified FNV.
• hash table: direct chaining: (C). Bro. David Carlson's tutorial and code (C++). linear probing hashing: insert (C), look up (C). Direct chaining: explanations, diagrams, and code (Visual Basic). Mark Nelson's tutorial to using C++ Hash Table Memoization: [for] Simplifying Dynamic Programming (C++).
• heap: Bro. David Carlson's heaps and heapsort tutorial and code (C++).
• heapsort: Prof. Dr. Hans Wener Lang's definitions, explanations, diagrams, and pseudo-code (Java), Bro. David Carlson's heaps and heapsort tutorial and code (C++). Paulo Roma's (Pascal) implementation. (Python). Worst-case behavior annotated for real time (WOOP/ADA), including bibliography.
• histogram sort: (C and Pascal).
• Huffman coding: build tree in array (C) -- also computes entropy and efficiency.
• ideal random shuffle: Discussion and explanation of what makes a shuffle ideal and two implementations (Haskell).
• independent set: (Fortran and C)
• insertion sort: An implementation (Java) due to Sedgewick and Wayne (search for Insertion sort). Algorithms and Data Structures' explanation and code (Java and C++). Other implementations may be available through the Stony Brook Algorithm Repository, Sorting. (Fortran). Flower Brackets using scanners, objects, and recursion (Java). (Python). use binary search to find where to insert (Python).
• internal sort: (Fortran)
• interpolation search: annotated for real time (WOOP/ADA), including bibliography. (Pascal)
• interpolation-sequential search: (Pascal) or (Pascal)
• inversion list: prototype code with tests (Perl).
• isomorphic: (C and Mathematica)
• Jaro-Winkler: Cohen, Ravikumar, and Fienberg have an implementation in their SecondString (Java) package.
• Johnson-Trotter: (C++, Java, C#)
• JSort: Pat Morin's implementation (Java).
• Karp-Rabin: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C), description and animation (C), (C and Pascal).
• k-ary Huffman coding: animation which counts characters, finds the code, encodes, and decodes (Java),
• k-d tree: C, C++, and Java, insert (C), range search (C), and search (C).
• KmpSkip Search: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• knapsack problem: Steven Skiena's Stony Brook Algorithm Repository (Fortran and Pascal). GAMS Class G2c3 (Fortran).
• knight's tour: Oleg Kiselyov's derivation (Prolog)
• Knuth-Morris-Pratt algorithm: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C). Terry R. McConnell's implementation of Unix strstr with KMP (C). (C and Pascal) which uses Boyer-Moore preprocessing (C)
• Kruskal's algorithm: analysis and code (C), (pseudocode)
• k-way merge: Jordan Zimmerman's k-way merge (Java).
• least common multiple: Flower Brackets (Java).
• leftist tree: merge and delete (C and Pascal) which use distance (C and Pascal), insert (C and Pascal)
• left rotation: (Pascal), (C). A great series of animations explaining rotations with code (Java).
• Lempel-Ziv-Welch: Mark Nelson's article with an explanation (C++)
• Levenshtein distance: Michael Gilleland's Levenshtein distance (Java, C++, Visual Basic), includes a great explanation and links to code in Perl, C, JavaScript, Python, and many more languages. Many implementations (Ada, C++, Lisp, Io, Java, OCaml, Octave, PHP, Python, Ruby, Visual Basic).
• linear probing: insert (C), search (C).
• linear probing sort: (C and Pascal).
• linear search: (Python). (C). Flower Brackets' implementation in (Java).
• linked list: Bro. David Carlson's tutorial and code (C++). Maksim Goleta's C# Collections uses it to implement queue (C#). Algorithms and Data Structures' explanation (Java and C++). Alexander Georgiev's singly linked list (Java), including a merge and parallel merge sorts.
• longest common subsequence: (C and Mathematica)
• longest common substring: (C and Mathematica)
• lower triangular matrix: (Fortran)
• matching: (Fortran, C, C++, and Pascal)
• matrix: (Fortran), (C++)
• maximally connected component: (C++, C, Java, and Mathematica)
• Maximal Shift: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• maximum-flow problem: Problem explanation and development of Ford-Fulkerson (pseudocode); including solving related problems, like multi-source, vertex capacity, bipartite matching, etc. description and links to implementations (C, Fortran, C++, Pascal, and Mathematica).
• median: select kth element (Pascal and C++)
• memoization: Mark Nelson's tutorial to using C++ Hash Table Memoization: [for] Simplifying Dynamic Programming (C++).
• merge sort: (Python). (C) that needs list merge (C) or array merge (C), (Pascal) that needs list merge (Pascal) or array merge (Pascal); Worst-case behavior annotated for real time (WOOP/ADA), including bibliography. Siegfried Sielaff's description and code of an in-place, stable variant he calls Swap Sort (C) (click the British flag for an English translation). Other implementations may be available through the Stony Brook Algorithm Repository, Sorting. Alexander Georgiev's merge sort (Java) implemented as part of a linked-list package. Includes a parallel merge sort, too. Flower Brackets (Java).
• metaphone: Many metaphone and double metaphone (Basic, C, Perl, and C++) implementations. Apache codec implementations of soundex, Metaphone, and Double Metaphone (Java).
• minimal perfect hashing: Description and code for minimal perfect hashing (C), mph: minimal perfect hash function generator (C). gperf: a near-minimal perfect hashing (C++), click on GNU mirror, click on a nearby server, then gperf.
• minimum spanning tree: (C++, Pascal, Fortran, C, and Mathematica). CALGO Algorithm 613 (Fortran).
• model checking: Model checkers: Spin and SMV.
• Morris-Pratt algorithm: Christian Charras' and Thierry Lecroq's explanation, visualization, references, and implementation (C).
• Munkres' assignment algorithm: Robert Pilgrim's example of step-wise coding of the algorithm (C#) from a description. Also available here.
• nearest neighbor: (C, C++, and Java)
• nondeterministic Turing machine: Alex Vinokur's Turing machine simulator (C++).
• Not So Naive: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• NP-complete: Stas Busygin's home page with QUALEX and SAT01 (C++).
• NYSIIS: (JavaScript) (in page source).
• optimal mismatch: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• ordered linked list: insert (C)
• oscillating merge sort: (Pascal)
• pagoda: delete (C and Pascal), insert (C and Pascal), and merge (C and Pascal)
• partition: generating partitions (Fortran, Mathematica, Pascal, and C).
• Patricia tree: Net-Patricia (Perl and C) is a C implementation with a Perl API. C prototyping tools, cprops (C), is a threaded implementation (find trie.c). py-radix (Python). insert (C), search (C).
• Pearson's hash: (C and Python). (Basic).
• perfect hashing: See the implementations at {minimal perfect hashing} and Gonnet and Baeza-Yates's insert (C), search (C) implementations.
• permutation: (Pascal, Fortran, Mathematica, and C); (Fortran). Mike Bostock's animations of different permutation algorithms with code (JavaScript). Ideal random shuffle (Haskell).
• pigeonhole sort: (Python).
• planar graph: draw a graph in the plane such that no edges cross (C, C++, Java, and Mathematica).
• polyphase merge sort: (C) (Error: variable some is not initialized nor reset) using an auxiliary function to select next file (C)
• Post machine: Alex Vinokur's Post machine simulator (C++).
• Prim-Jarnik algorithm: explanation and implementation (pseudocode and Java bytecode)
• priority queue: Links to implementations, dozens of papers, introductory material, etc..
• pseudo-random number generator: (C++, C, and Java). GAMS (C). Using C libraries to get random numbers in a certain range (C) is C FAQ question 13.16, C FAQ question 12.9 as of 1995 (C), or section 7.8.7 (C) of Steve Summit's Notes to Accompany The C Programming Language.
• P-tree: Implementations of P-tree (1) insert (C and Pascal), delete max (C and Pascal), and head (C and Pascal)
• qm sort: Pat Morin's implementation (Java).
• q sort: Pat Morin's implementation (Java). Apple Opensource qsort (C).
• quadratic probing: insert (C and Pascal)
• quadtree: insert (C), search (C).
• quad trie: insert (C), search (C)
• queue: Maksim Goleta's C# Collections linked-list implementation (C#). Bro. David Carlson's tutorial and code (C++) using linked list.
• quick search: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• quicksort: (Python). Wikipedia entry with extended discussion and alternatives (C, Python, Haskell, pseudocode). explanation (Java and C++). Flower Brackets explanation, including code and complexity (Java).
• radix sort: (C and Pascal). John Morris' analysis, explanation, and code (C). tutorial with examples and code (C++). (Python).
• Raita: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• randomized binary search tree: Oleg Kiselyov's treap implementation (Scheme) and verification code and other links.
• rapid sort: Patrick Eberhart's description and illustration (Visual Basic and C++).
• reachable: Single-source and multiple-source reachability algorithms (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• rebalance: (Pascal)
• rectangular matrix: (Fortran)
• red-black tree: analysis, explanation, examples, and code (C). Ben Pfaff's libavl (C) including pointers to other implementations.
• reservoir sampling: (Perl).
• Reverse Colussi: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Reverse Factor: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• right rotation: (C and Pascal). A great series of animations explaining rotations with code (Java).
• right-threaded tree: Ben Pfaff's explanations and code (C)
• R^*-tree: In Marios Hadjieleftheriou's Spatial Index Library (C++)
• R-tree: (1) Ondřej Pavlata's Mg R-tree library(C++).
• select and partition: Vladimir Zabrodsky's analysis and comparison (Rexx)
• selection sort: Thomas Baudel's links to animation (Java). Simple Programming Tutorials' explanation (Java and C++). Flower Brackets explanation (Java). (Python).
• select mode: (Pascal)
• separate chaining: insert (C), search (C).
• set: (C++ and Pascal). Maksim Goleta's C# Collections sorted set (C#).
• set cover: (Pascal)
• set packing: (Pascal)
• Shell sort: Worst-case behavior annotated for real time (WOOP/ADA), including bibliography. Pat Morin's implementation (Java). (Python). scroll down to ALGORITHM AS 304.8 (Fortran), (Forth), strings (Basic).
• Shift-Or: explanation and code (C)
• shortest common superstring: (C)
• shortest path: (C, C++, Pascal, Fortran, and Mathematica)
• sieve of Eratosthenes: (Python). Peter Luschny's (Java 5 and C#) implementation.
• Simon's algorithm: In Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms preprocessing phase (C)
• single-destination shortest-path problem: See implementations at graph.
• single-source shortest-path problem: See implementations at graph. Single-source shortest directed path (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• skip list: Code (C) at ePaperPress.
• skip search: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Smith algorithm: visualization and code (C)
• Smith-Waterman algorithm: Ahmed Moustafa's implementation in JAligner (Java).
• smoothsort: Smoothsort, an alternative for sorting in situ typescript (guarded command language)
• sort: Specific implementations can be found under the specific sort routines or at (Pascal, C++, Fortran, and Mathematica). Thomas Baudel's sort algorithm visualizer (Java) with a dozen algorithms.
• sorted array: Insert (C).
• sorted list: insertion (C) into an ordered linked list.
• soundex: (C). Apache codec implementations of soundex, Metaphone, and Double Metaphone (Java). (Visual Basic).
• sparse matrix: Input/output for sparse matrices stored in Harwell-Boeing Format (C)
• square root: GAMS Class C2 has many implementations of powers, roots, and reciprocals (C and Fortran). Many variations (C and Assembler) for caching, pipelined processing, etc.
• stack: Maksim Goleta's C# Collections linked-list implementation (C#). Bro. David Carlson's tutorial and code (C++).
• star encoding: Mark Nelson's 2002 Star-Encoding (C++), includes a similar algorithm that assigns shorter codes to more frequent words.
• Steiner tree: (C and Pascal).
• stooge sort: Pat Morin's implementation (Java). (Python).
• string matching: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C), (C++ and Pascal), Strmat (C) - a collection of string matching and pattern discovery programs, (Fortran), (Fortran).
• string matching on ordered alphabets: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• string matching with errors: See implementations at {string matching}. Steven Skiena's Stony Brook Algorithm Repository (C and Pascal)
• strongly connected component: (C++, C, Java, and Mathematica)
• strongly connected graph: (C++, C, Java, and Mathematica)
• subset: generating subsets (Fortran, Mathematica, and Pascal)
• suffix array: Steven Skiena's Suffix Trees and Arrays (C++, Python, and Java).
• suffix tree: Strmat - a variety of string matching and pattern discovery algorithms (C). Christian Kreibich's libstree (C) including depth- and breadth-first traversal, string update, and examples like LCS. Mark Nelson's great Fast String Searching With Suffix Trees (C++) explains Ukkonen's linear-time algorithm. Dr. Dobb's Journal, August, 1996. Steven Skiena's Suffix Trees and Arrays (C++, Python, and Java).
• temporal logic: The SMV model checker.
• ternary search tree: Richard McGraw's explanation, example, and links to other implementations (C++, Java) and his implementations called ctst-dist-0.30.tar.* (C). Ternary Search Tree Dictionary in (C#): Faster String Dictionary! by Jonathan de Halleux.
• threaded tree: Ben Pfaff's explanations and code (C)
• top-down radix sort: (C and Pascal)
• topological sort: Eric Lippert's narrative example and solution (JScript). (C++, Mathematica, C, and Pascal) (Python). topological sort for directed graphs (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• towers of Hanoi: (Python). (JavaScript)
• transitive closure: Steven Skiena's Algorist/Stony Brook summary and links to implementations (C++, Java, and Mathematica). (Java) from Sedgewick and Wayne "Algorithms" 4th edition.
• transitive reduction: Steven Skiena's Algorist/Stony Brook summary and links to implementations (C++, Java, and Mathematica).
• transpose sequential search: (C)
• traveling salesman: Steven Skiena's Stony Brook Algorithm Repository (C, Fortran, Pascal, Mathematica, and C++). Animation and implementation (Icon).
• treap: Oleg Kiselyov's (Scheme) and verification code and other links.
• treesort (1): (C)
• trie: insert (C) and search (C).
• Turbo-BM: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Turbo Reverse Factor: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• Turing machine: Alex Vinokur's Turing machine simulator (C++).
• Two Way algorithm: Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)
• union of automata: (C)
• unranking: (C). (Delphi?). Wendy Myrvold and Frank Ruskey, Ranking and Unranking Permutations in Linear Time, 13 April 2000, give linear time ranking and unranking algorithms.
• upper triangular matrix: (Fortran)
• vertex coloring: (Fortran, C, Pascal, C++, and Mathematica)
• vertex connectivity: Steve Skiena's Stony Brook Algorithm Repository (C, C++, Java, and Mathematica)
• vertex cover: (C, Fortran, and Mathematica)
• Vitter's algorithm: Algorithm 673 in plain text (Pascal).
• Zeller's congruence: Dr J R Stockton's The Calendrical Works of Rektor Chr. Zeller: The Day-of-Week and Easter Formulae page has implementations of Zeller's congruence, for day-of-week (Pascal, JavaScript). The page includes tests and code for Easter, Zeller's original papers (and translations), etc. The following is only correct for Gregorian dates: Comp.lang.c FAQ question 17.28 (C).
• Zhu-Takaoka: explanation, animation, and example (C)