This is the web page of terms with definitions organized by type. That is, whether the term is an algorithm, a definition, a problem, or data structure. We also list all entries with links to implementations and entries by area, for instance, graphs, trees, sorting, etc.

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Run on Mon May 11 15:07:56 2026

Types

• Definitions
• Algorithmic Techniques
• Classic Problems
• Algorithms
• Data Structures
• Entries with No Type

Definitions

• ω
• Ω
• ∼
• Θ
• absolute performance guarantee
• abstract data type
• accepting state
• acyclic directed graph
• acyclic graph
• adaptive sort
• adjacent
• admissible vertex
• ADT
• adversary
• algorithm
• algorithmically solvable
• alphabet
• alternating path
• alternating Turing machine
• alternation
• amortized cost
• ancestor
• and
• ANSI
• antichain
• antisymmetric
• arborescence
• arc
• array index
• articulation point
• associative
• asymptotically tight bound
• asymptotic bound
• asymptotic space complexity
• asymptotic time complexity
• asymptotic upper bound
• augmenting path
• automaton
• average case
• average-case cost
• axiomatic semantics
• balance
• Benford's law
• best case
• best-case cost
• biconnected component
• biconnected graph
• big-O notation
• binary function
• binary relation
• bipartite graph
• bipartite matching
• bisector
• block
• blocking flow
• blossom
• boolean
• boolean expression
• boolean function
• border
• bottom-up tree automaton
• boundary-based representation
• bounded error probability in polynomial time
• BPP
• Bradford's law
• bridge
• bucket
• bucketing method
• Calculus of Communicating Systems
• candidate consistency testing
• candidate verification
• canonical complexity class
• capacity
• capacity constraint
• CCS
• cell probe model
• cellular automaton
• centroid
• certificate
• chain
• child
• chromatic index
• chromatic number
• circuit
• circuit complexity
• circuit value problem
• clique
• clustering
• clustering free
• coarsening
• codeword
• collision
• Communicating Sequential Processes
• commutative
• comparison sort
• competitive analysis
• competitive ratio
• complement
• complete graph
• completely connected graph
• complexity
• complexity class
• compound algorithm
• computable
• concave function
• concurrent flow
• concurrent read, concurrent write
• concurrent read, exclusive write
• confluently persistent data structure
• conjunction
• connected components
• connected graph
• constant function
• Cook reduction
• Cook's theorem
• covering
• CRCW
• CREW
• CSP
• CTL
• cut
• cutting plane
• cutting theorem
• cut vertex
• cycle
• D-adjacent
• DAG
• data structure
• decidable language
• decidable problem
• decision problem
• decomposable searching problem
• degree
• dense graph
• depoissonization
• depth
• descendant
• deterministic
• deterministic finite automaton
• deterministic finite state machine
• deterministic finite tree automaton
• deterministic pushdown automaton
• deterministic tree automaton
• DFA
• DFS forest
• DFTA
• diagonalization
• diameter
• dichotomic search
• difference
• directed acyclic graph
• disjoint set
• disjunction
• distributional complexity
• domain
• don't care
• DPDA
• dual
• dual linear program
• dynamic
• edge
• edge coloring
• edge connectivity
• edge crossing
• edge-weighted graph
• edit distance
• edit operation
• edit script
• efficiency
• end-of-string
• ERCW
• EREW
• Euclidean distance
• Euclidean Steiner tree
• Euler cycle
• Eulerian graph
• Eulerian path
• Euler's formula
• exclusive or
• exclusive read, concurrent write
• exclusive read, exclusive write
• existential state
• expander graph
• exponential
• external node
• external sort
• extremal
• extreme point
• factor
• factorial
• feasible region
• feasible solution
• feedback edge set
• feedback vertex set
• Fibonacci number
• finite state automaton
• finite state machine
• finite state transducer
• first come, first served
• first-in, first-out
• fixed-grid method
• flow
• flow conservation
• flow function
• flow network
• forest
• forest editing problem
• formal language
• formal methods
• formal verification
• fractional solution
• free edge
• free tree
• free vertex
• full array
• fully dynamic graph problem
• fully persistent data structure
• function
• gamma function
• geometric optimization problem
• global optimum
• graph coloring
• graph concentration
• Gray code
• grid drawing
• Hamiltonian cycle
• Hamiltonian path
• Hamming distance
• Hausdorff distance
• head
• heap property
• height
• homeomorphic
• horizontal visibility map
• hybrid algorithm
• hyperedge
• implication
• implies
• inclusion-exclusion principle
• inclusive or
• incompressible string
• in-degree
• independent set
• information theoretic bound
• integer linear program
• integer multi-commodity flow
• integer polyhedron
• interactive proof system
• interior-based representation
• internal node
• internal sort
• intersection
• intractable
• irreflexive
• isomorphic
• jsort
• Karp reduction
• k-coloring
• k-connected graph
• k-dimensional
• K-dominant match
• key
• Königsberg bridges problem
• Kolmogorov complexity
• Kraft's inequality
• Kripke structure
• kth order Fibonacci numbers
• k-way merge
• labeled graph
• language
• last-in, first-out
• lattice
• layered graph
• LCM
• leaf
• least common multiple
• level
• Levenshtein distance
• lexicographical order
• linear
• linear order
• linear product
• linear program
• link
• list contraction
• little-o notation
• L_m distance
• load factor
• local alignment
• local optimum
• logarithmic
• Lotka's law
• lower bound
• lowest common ancestor
• l-reduction
• Manhattan distance
• many-one reduction
• Marlena
• Master theorem
• matched edge
• matched vertex
• matching
• matrix multiplication
• max-heap property
• maximally connected component
• maximum bipartite matching
• MBB
• Mealy machine
• mean
• median
• meld
• merge
• midrange
• min-heap property
• minimum bounding box
• minimum cut
• minimum spanning tree
• minimum vertex cut
• Minkowski distance
• mixed integer linear program
• mode
• model of computation
• moderately exponential
• monotonically decreasing
• monotonically increasing
• Moore machine
• move
• MST
• multi-commodity flow
• multiprocessor model
• multiway decision
• multiway merge
• nand
• n-ary function
• NC many-one reducibility
• negation
• network flow
• next state
• NFA
• NFTA
• NIST
• node
• nondeterministic
• nondeterministic finite automaton
• nondeterministic finite state machine
• nondeterministic finite tree automaton
• nondeterministic polynomial time
• nondeterministic tree automaton
• nondeterministic Turing machine
• nonterminal node
• nor
• not
• NP
• NP-complete
• NP-complete language
• NP-hard
• nullary function
• null tree
• O
• objective function
• occurrence
• off-line algorithm
• offset
• omega
• omicron
• 1-based indexing
• one-dimensional
• on-line algorithm
• optimal
• optimal cost
• optimal solution
• optimal value
• optimization problem
• or
• oracle set
• oracle tape
• oracle Turing machine
• order
• oriented acyclic graph
• oriented tree
• orthogonal drawing
• orthogonally convex rectilinear polygon
• out-degree
• P
• packing
• padding argument
• PAM
• parallel computation thesis
• parallel random-access machine
• parent
• partial function
• partially decidable problem
• partially dynamic graph problem
• partially ordered set
• partially persistent data structure
• partial order
• partial recursive function
• partition
• path
• pattern
• pattern element
• P-complete
• PDA
• perfect binary tree
• perfect k-ary tree
• perfect matching
• performance guarantee
• performance ratio
• persistent data structure
• planar graph
• planarization
• planar straight-line graph
• point access method
• pointer jumping
• pointer machine
• poissonization
• polychotomy
• polyhedron
• polylogarithmic
• polynomial
• polynomial hierarchy
• polynomial time
• polynomial-time reduction
• polytope
• poset
• potential function
• PRAM
• predicate
• prefix
• prefix code
• primary clustering
• primitive algorithm
• primitive recursive
• principle of optimality
• probabilistic algorithm
• probabilistically checkable proof
• probabilistic Turing machine
• probe sequence
• procedure
• process algebra
• proper
• proper coloring
• proper subset
• pth order Fibonacci numbers
• purely functional language
• pushdown automaton
• pushdown transducer
• quadtree complexity theorem
• quantum computation
• random access machine
• randomized algorithm
• randomized complexity
• randomized polynomial time
• range
• rank
• reachable
• recognizer
• rectilinear
• rectilinear Steiner tree
• recurrence equations
• recurrence relation
• recursion termination
• recursion tree
• recursive data structure
• recursive doubling
• recursive language
• recursively enumerable language
• recursively solvable
• reduced basis
• reduced digraph
• reduction
• reflexive
• regular decomposition
• relation
• relative performance guarantee
• relaxation
• relaxed balance
• rescalable
• restricted universe sort
• Rice's method
• root
• root balance
• rooted tree
• rotation
• rough graph
• RP
• run time
• SAM
• saturated edge
• search tree property
• secondary clustering
• segment
• self-loop
• semidefinite programming
• separation theorem
• shared memory
• shortcutting
• shortest spanning tree
• sibling
• signature
• simple path
• simple uniform hashing
• simplex
• simulation theorem
• single program multiple data
• singularity analysis
• sink
• skew symmetry
• solvable
• source
• space-constructible function
• spanning tree
• sparse graph
• sparsity
• spatial access method
• SPMD
• SST
• stable
• stack tree
• star-shaped polygon
• start state
• state
• state machine
• state transition
• static
• s-t cut
• Steiner point
• Steiner ratio
• Steiner tree
• Steiner vertex
• Stirling's approximation
• Stirling's formula
• straight-line drawing
• strictly decreasing
• strictly increasing
• string editing problem
• strongly connected component
• strongly connected graph
• strongly NP-hard
• subadditive ergodic theorem
• subgraph
• sublinear time algorithm
• subsequence
• subset
• substring
• subtree
• suffix
• suffix automaton
• superimposed code
• superset
• supersink
• supersource
• symmetric
• symmetric set difference
• tail
• target
• temporal logic
• terminal
• terminal node
• text
• theta
• three-dimensional
• time-constructible function
• time/space complexity
• top-down tree automaton
• topological order
• topological sort
• topology tree
• total function
• totally decidable language
• totally decidable problem
• totally undecidable problem
• total order
• tour
• tractable
• transition
• transition function
• transitive
• transitive closure
• transitive reduction
• tree automaton
• tree contraction
• tree editing problem
• tree traversal
• triangle inequality
• triconnected graph
• trinary function
• Turing machine
• Turing reduction
• Turing transducer
• two-dimensional
• unary function
• uncomputable function
• uncomputable problem
• undecidable language
• undecidable problem
• uniform circuit complexity
• uniform circuit family
• union
• universal hashing
• universal state
• universal Turing machine
• universe
• unsolvable problem
• unsorted list
• Venn diagram
• vertex
• vertex coloring
• vertex connectivity
• vertical visibility map
• visibility map
• visible
• walk
• WCET
• weighted, directed graph
• weighted graph
• window
• witness
• work
• work-depth model
• work-efficient
• work-preserving
• worst case
• worst-case cost
• worst-case execution time
• worst-case minimum access
• xor
• Yule distribution
• 0-ary function
• 0-based indexing
• Zipfian distribution
• Zipf's law
• ZPP

Algorithmic Techniques

• ρ-approximation algorithm
• approximation algorithm
• backtracking
• branch and bound
• British Museum technique
• brute force
• collective recursion
• decimation
• deterministic algorithm
• divide and conquer
• divide and marriage before conquest
• dynamic programming
• dynamization transformation
• easy split, hard merge
• exhaustive search
• fathoming
• fully polynomial approximation scheme
• greedy algorithm
• greedy heuristic
• hard split, easy merge
• heuristic
• iteration
• Las Vegas algorithm
• memoization
• metaheuristic
• Monte Carlo algorithm
• nondeterministic algorithm
• parametric searching
• pipelined divide and conquer
• polynomial approximation scheme
• prune and search
• PTAS
• randomization
• random sampling
• recursion
• sparsification
• symmetry breaking
• tail recursion

Classic Problems

• all pairs shortest path
• all simple paths
• array search
• assignment problem
• binary knapsack problem
• bin packing problem
• bottleneck traveling salesman
• busy beaver
• Byzantine generals
• capacitated facility location
• Chinese postman problem
• clique problem
• Collatz problem
• continuous knapsack problem
• critical path problem
• cutting stock problem
• dining philosophers
• discrete p-center
• Dutch national flag
• 8 queens
• element uniqueness
• Euclidean traveling salesman problem
• exact string matching
• facility location
• find k^th least element
• finite state machine minimization
• fractional knapsack problem
• graph drawing
• graph isomorphism
• graph partition
• halting problem
• heaviest common subsequence
• knapsack problem
• knight's tour
• k^th shortest path
• k^th smallest element
• LCS
• longest common subsequence
• longest common substring
• marriage problem
• matrix-chain multiplication problem
• maximal independent set
• maximum-flow problem
• nearest neighbor
• network flow problem
• n queens
• optimal polygon triangulation problem
• optimal triangulation problem
• path system problem
• PCP
• phonetic coding
• Post's correspondence problem
• prisoner's dilemma
• select and partition
• selection problem
• select k^th element
• set cover
• set packing
• shortest common supersequence
• shortest common superstring
• shortest path
• single-destination shortest-path problem
• single-pair shortest-path problem
• single-source shortest-path problem
• slope selection
• string matching
• string searching
• strip packing
• subgraph isomorphism
• text searching
• towers of Hanoi
• traveling salesman
• TSP
• UKP
• unbounded knapsack problem
• vehicle routing problem
• vertex cover
• VRP
• 0-1 knapsack problem

Algorithms

• α
• Ackermann's function
• adaptive heap sort
• adaptive Huffman coding
• address-calculation sort
• Aho-Corasick
• algorithm BSTW
• algorithm FGK
• Alpha Skip Search algorithm
• American flag sort
• Apostolico-Crochemore
• Apostolico-Giancarlo algorithm
• approximate string matching
• arithmetic coding
• array merging
• balanced k-way merge sort
• balanced merge sort
• balanced multiway merge
• balanced quicksort
• balanced two-way merge sort
• Batcher sort
• Baum Welch algorithm
• BBP algorithm
• Bellman-Ford algorithm
• best-first search
• bidirectional bubble sort
• binary GCD
• binary insertion sort
• binary search
• bingo sort
• bin sort
• bitonic sort
• blind sort
• block search
• bogosort
• Bond Sequential Search
• Boruvka's algorithm
• Boyer-Moore
• Boyer-Moore-Horspool
• bozo sort
• breadth-first search
• Bresenham's algorithm
• brick sort
• brute force string search
• brute force string search with mismatches
• bubble sort
• bucket sort
• buddy system
• build-heap
• Burrows-Wheeler transform
• BWT
• Caverphone
• Chinese remainder theorem
• Christofides algorithm
• cocktail shaker sort
• collision resolution scheme
• Colussi
• combination
• comb sort
• Commentz-Walter
• CORDIC
• counting sort
• CRC
• cube root
• Cupif-Giannini tree traversal
• cyclic redundancy check
• DAG shortest paths
• depth-first search
• derangement
• deterministic finite automata string search
• deterministic random bit generator
• Deutsch-Jozsa algorithm
• DFS
• Dijkstra's algorithm
• diminishing increment sort
• distribution sort
• distributive partitioning sort
• dominance tree sort
• Doomsday rule
• double-direction bubble sort
• double hashing
• double metaphone
• DRBG
• dual-pivot quicksort
• dynamic Huffman coding
• Euclidean algorithm
• Euclid's algorithm
• exchange sort
• extended Euclid's algorithm
• external memory algorithm
• external merge
• external quicksort
• external radix sort
• extrapolation search
• fast fourier transform
• Ferguson-Forcade algorithm
• FFT
• Fibonaccian search
• Find
• finite Fourier transform
• Fisher-Yates shuffle
• flash sort
• Floyd-Warshall algorithm
• Ford-Bellman
• Ford-Fulkerson method
• frequency count heuristic
• Galil-Giancarlo
• Galil-Seiferas
• GCD
• gnome sort
• greatest common divisor
• Grover's algorithm
• hash
• hash function
• hash table delete
• heapify
• heapsort
• highest common factor
• histogram sort
• Horner's rule
• Horspool
• hsadelta
• Huffman coding
• Hungarian algorithm
• ideal merge
• ideal random shuffle
• in-order traversal
• in-place sort
• insertion sort
• interpolation search
• interpolation-sequential search
• interpolation sort
• introsort
• introspective sort
• inverse Ackermann function
• Jaro-Winkler
• Johnson's algorithm
• Johnson-Trotter
• JSort
• J sort
• jump search
• Karnaugh map
• Karp-Rabin
• k-ary Huffman coding
• KMP
• KmpSkip Search
• Knuth-Morris-Pratt algorithm
• Kruskal's algorithm
• KV diagram
• k-way merge sort
• LCFS hashing
• left rotation
• Lempel-Ziv-Welch
• level-order traversal
• linear congruential generator
• linear hash
• linear insertion sort
• linear probing sort
• linear search
• locality-sensitive hashing
• lucky sort
• LZW compression
• Malhotra-Kumar-Maheshwari blocking flow
• Maximal Shift
• merge sort
• metaphone
• Miller-Rabin
• minimal perfect hashing
• minimax
• model checking
• MODIFIND
• Morris-Pratt algorithm
• move-to-front heuristic
• move-to-root heuristic
• multiplication method
• multiprefix
• Munkres' assignment algorithm
• naive string search
• nonbalanced merge
• nonbalanced merge sort
• Not So Naive
• NYSIIS
• open addressing
• optimal hashing
• optimal merge
• optimal mismatch
• optimal polyphase merge
• optimal polyphase merge sort
• order-preserving hash
• order-preserving Huffman coding
• order-preserving minimal perfect hashing
• oscillating merge sort
• parallel prefix computation
• Pearson's hash
• perfect hashing
• perfect shuffle
• permutation
• pigeonhole sort
• polyphase merge
• polyphase merge sort
• postfix traversal
• postman's sort
• postorder traversal
• prefix sums
• prefix traversal
• preorder traversal
• Prim-Jarnik algorithm
• PRNG
• pseudo-random number generator
• p-way merge sort
• qm sort
• q sort
• quadratic probing
• quick search
• quicksort
• Rabin-Karp
• radix sort
• Raita
• randomized rounding
• random number generator
• random search
• range sort
• rapid sort
• Ratcliff/Obershelp pattern recognition
• rebalance
• rehashing
• repeated squaring
• reservoir sampling
• Reverse Colussi
• Reverse Factor
• right rotation
• RNG
• Robin Hood hashing
• rotate left
• rotate right
• scan
• scapegoat tree
• Schorr-Waite graph marking algorithm
• search
• secant search
• Select
• selection sort
• select mode
• self-organizing sequential search
• sequential search
• shadow merge
• shadow merge insert
• shaker sort
• Shannon-Fano coding
• Shell sort
• Shift-Or
• Shor's algorithm
• shuffle
• shuffle sort
• sieve of Eratosthenes
• sift up
• Simon's algorithm
• simple merge
• simulated annealing
• sinking sort
• skip search
• Smith algorithm
• Smith-Waterman algorithm
• smoothsort
• sort
• sort in place
• soundex
• space ordering method
• square root
• star encoding
• static Huffman coding
• Steinhaus-Johnson-Trotter
• stooge sort
• strand sort
• string matching on ordered alphabets
• string matching with errors
• string matching with mismatches
• strsrch
• stupid sort
• tabulation hashing
• taco sort
• three-way merge sort
• top-down radix sort
• tournament
• tournament sort
• transpose sequential search
• treesort (1)
• treesort (2)
• tripartition
• Turbo-BM
• Turbo Reverse Factor
• twisted tabulation hashing
• Two Way algorithm
• two-way merge sort
• uniform hashing
• union of automata
• UnShuffle sort
• Veitch diagram
• Viterbi algorithm
• Vitter's algorithm
• weak-heap sort
• Zeller's congruence
• Zhu-Takaoka

Data Structures

• (a,b)-tree
• active data structure
• adaptive k-d tree
• adjacency-list representation
• adjacency-matrix representation
• array
• association list
• associative array
• AVL tree
• bag
• balanced binary search tree
• balanced binary tree
• balanced multiway tree
• balanced tree
• BANG file
• BB(α) tree
• BDD
• BD-tree
• binary heap
• binary priority queue
• binary search tree
• binary tree
• binary tree representation of trees
• binomial heap
• binomial tree
• bintree
• bit vector
• B_k tree
• blind trie
• block addressing index
• Bloom filter
• bounded queue
• bounded stack
• B⁺-tree
• BSP-tree
• B*-tree
• B-tree
• bucket array
• bucket trie
• buddy tree
• BV-tree
• cactus stack
• calendar queue
• cartesian tree
• cell tree
• chaining
• circular list
• circular queue
• coalesced chaining
• coding tree
• compact DAWG
• compact trie
• complete binary tree
• complete tree
• cuckoo hashing
• DAWG
• deque
• dictionary
• diet
• digital search tree
• digital tree
• digraph
• direct chaining
• directed acyclic word graph
• directed graph
• discrete interval encoding tree
• double-ended priority queue
• doubly-chained tree
• doubly-ended queue
• doubly linked list
• D-tree
• dyadic tree
• dynamic array
• dynamic hashing
• elastic-bucket trie
• enfilade
• EXCELL
• extended binary tree
• extended k-d tree
• extendible hashing
• external chaining
• external index
• external memory data structure
• Fibonacci heap
• Fibonacci tree
• FIFO
• filial-heir chain
• finitary tree
• first child-next sibling binary tree
• forward index
• full binary tree
• full inverted index
• functional data structure
• GBD-tree
• graph
• grid file
• hashbelt
• hash heap
• hash table
• hash tree
• hB-tree
• heap
• height-balanced binary search tree
• height-balanced tree
• hidden Markov model
• HMM
• huge sparse array
• hypergraph
• IBLT
• incremental hashing
• index file
• inverse suffix array
• inversion list
• inverted file index
• inverted index
• invertible Bloom lookup table
• jelly-fish
• jump list
• k-ary heap
• k-ary tree
• k-d-B-tree
• k-d tree
• k-way tree
• leftist tree
• LIFO
• linear hashing
• linear probing
• linear quadtree
• linked list
• list
• lower triangular matrix
• map
• Markov chain
• matrix
• Merkle tree
• monotone priority queue
• multigraph
• multilayer grid file
• multi-set
• multi suffix tree
• multiway search tree
• multiway tree
• octree
• ordered array
• ordered linked list
• ordered tree
• oriented graph
• orthogonal lists
• pagoda
• passive data structure
• Patricia tree
• pile
• PLOP-hashing
• priority queue
• proper binary tree
• property list
• P-tree
• quadtree
• quad trie
• queue
• radix tree
• ragged matrix
• randomized binary search tree
• randomized search tree
• RBST
• rectangular matrix
• recursive
• red-black tree
• reduced ordered binary decision diagram
• relational structure
• R-file
• right-threaded tree
• ROBDD
• R⁺-tree
• R^*-tree
• R-tree
• saguaro stack
• SBB tree
• scatter storage
• search tree
• self-organizing list
• separate chaining
• set
• shadow heap
• singly linked list
• skd-tree
• skip list
• sorted array
• sorted list
• sparse matrix
• spiral storage
• splay tree
• square matrix
• stack
• st-digraph
• strictly lower triangular matrix
• strictly upper triangular matrix
• string
• suffix array
• suffix tree
• symmetrically linked list
• symmetric binary B-tree
• ternary search tree
• threaded binary tree
• threaded tree
• treap
• tree
• trie
• TST
• twin grid file
• 2-choice hashing
• 2-left hashing
• two-level grid file
• 2-3-4 tree
• 2-3 tree
• two-way linked list
• UB-tree
• undirected graph
• uniform matrix
• universal B-tree
• unlimited branching tree
• upper triangular matrix
• van Emde-Boas priority queue
• weak-heap
• weight-balanced tree
• zipper

Entries with No Type

• cascade merge sort
• division method
• double left rotation
• double right rotation
• expandable hashing
• interval tree
• k-clustering
• minimum path cover
• multikey Quicksort
• OBDD
• oblivious algorithm
• ordered binary decision diagram
• pairing heap
• path cover
• Post machine
• prefix computation
• Randomized-Select
• result cache
• three-way radix quicksort
• virtual hashing

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