cp-templates :: index

00 BASE

Base

Templete/ the scaffold everything else pastes into 3

call	trigger	what it does	cx	src	file
BASE01	normal	base template: macros, fast IO, debug include`type normal, Tab -- everything else assumes this ran first`		house	cpp.snippets
BASE02	PBDS	order-statistics set/map -- kth element, count-less-than`s.find_by_order(1); s.order_of_key(4);`	O(log n)	standard	PBDS.cpp
BASE03	debug.hpp	colored pretty-printer for containers, pairs, tuples`debug(v); debugi(arr); debugg(adj);`		house	debug.hpp

01 GR

Graphs

Graphs/ shortest paths, connectivity, flow, decomposition 10

call	trigger	what it does	cx	src	file
GR01	DSU	disjoint-set union, path compression + union by size`DSU d(n); d.unite(u, v); d.connected(u, v); d.compSize(u);`	O(a(n))	house	DSU.cpp
GR02	Dijkstra	shortest paths, non-negative weights`Dijkstra dj(n); dj.addEdge(u, v, w); dj.run(src); dj.dist[v];`	O((n+m) log n)	house	Dijkstra.cpp
GR03	BellmanFord	shortest paths with negative weights + cycle detection`BellmanFord bf(n); bf.addEdge(u, v, w); bf.run(src); bf.dist[v];`	O(n*m)	KACTL	BellmanFord.cpp
GR04	BinaryLift	LCA, kth ancestor, distance via binary lifting`bl.addEdge(u, v); bl.init(); bl.lca(u, v); bl.dist(u, v); bl.kthAncestor(u, k);`	O(log n) qry	KACTL	BinaryLifting.cpp
GR05	SCC	Tarjan's strongly connected components, iterative`scc.addEdge(u, v); scc.run(); scc.comp[v]; scc.sccCount;`	O(n+m)	KACTL	SCC.cpp
GR06	Bridges	bridges + articulation points in one DFS`ba.addEdge(u, v); ba.run();`	O(n+m)	KACTL	BridgesArticulation.cpp
GR07	TopoSort	topological sort, Kahn's algorithm`vector<vector<int>> adj(n); auto order = topoSort(n, adj);`	O(n+m)	KACTL	TopoSort.cpp
GR08	HLD	heavy-light decomposition for path queries`hld.addEdge(u, v); hld.build(); hld.lca(u, v); hld.process(u, v, [&](int l, int r) {...});`	O(log^2 n)	KACTL	HLD.cpp
GR09	Centroid	centroid decomposition of a tree`cd.addEdge(u, v); cd.build(); cd.centroidParent[v];`	O(n log n)	cp-algo	CentroidDecomposition.cpp
GR10	Dinic	max flow, Dinic's algorithm`Dinic dn(n); dn.addEdge(u, v, c); int f = dn.maxflow(s, t);`	O(E sqrt V)	KACTL	Dinic.cpp

02 TR

Trees

Trees/ weighted-tree path queries 1

call	trigger	what it does	cx	src	file
TR01	WeightedLCA	LCA + weighted path distance via binary lifting`wl.lca(u,v); wl.dist(u,v);`	O(log n)	house	WeightedLCA.cpp

03 ST

Strings

Strings/ matching automata, suffix structures, hashing 5

call	trigger	what it does	cx	src	file
ST01	ZFunction	Z-function + pattern occurrences`ZFunction::findOccurrences(p,t);`	O(n)	cp-algo	ZFunction.cpp
ST02	KMP	prefix-function string matching`kmp.match(text);`	O(n+m)	KACTL	KMP.cpp
ST03	SuffixArray	suffix array + Kasai's LCP`sa.sa[i]; sa.rnk[i]; sa.lcp[i];`	O(n log n)	KACTL	SuffixArray.cpp
ST04	AhoCorasick	multi-pattern matching automaton`ac.addPattern(p); ac.countMatches(t);`	O(n+m+z)	KACTL	AhoCorasick.cpp
ST05	PolyHash	anti-hash-test-safe polynomial hash, string or array`h.get(l,r); h.combine(lh,rh,rlen);`	O(1) qry	house	PolyHash.cpp

04 MA

Math

Maths/ modular arithmetic, combinatorics, number theory 8

call	trigger	what it does	cx	src	file
MA01	ModInt	modular integer type with operators`mint a = 2; cout << power(a, 3) << a / 5; using mint2 = Modular<1000000007>;`	O(log MOD)	house	ModInt.cpp
MA02	nCr	nCr/nPr, auto-ready, sized to the base template's N`fac.ncr(n,r); // instantiated as fac`	O(1) qry	house	cpp.snippets
MA03	Comb	nCr/nPr with a custom max-N`Combinatorics C(maxN); C.nCr(a, b); C.nPr(a, b);`	O(1) qry	house	Combinatorics.cpp
MA04	CRT	Chinese Remainder Theorem, two congruences`auto [x, L] = crt(a, m, b, n);`	O(log)	KACTL	CRT.cpp
MA05	Totient	Euler's totient of a single value`int f = phi(n);`	O(sqrt n)	cp-algo	Totient.cpp
MA06	FastPow	binary exponentiation + inverse, runtime modulus`FastPow::power(b, e, m); FastPow::inverse(n, m);`	O(log e)	house	FastPow.cpp
MA07	NTT	polynomial multiplication mod 998244353`vector<int> c = NTT::multiply(a, b);`	O(n log n)	KACTL	NTT.cpp
MA08	Sieve	linear sieve, primality + factorization`Sieve sv(n); sv.isPrime(x); sv.factorize(x); sv.primes;`	O(N) build	cp-algo	primes.cpp

05 SG

Segment trees

SegmentTree/ range query / range update, five variants 6

call	trigger	what it does	cx	src	file
SG01	SegTree	iterative point-update range-query, generic op`st.update(i,val); st.query(l,r);`	O(log n)	house	SegmentTree.cpp
SG02	LazySegTree	range-update range-query, generic op`st.Add(l,r,v); st.Sum(l,r);`	O(log n)	house	LazySegmentTree.cpp
SG03	PersistentSegTree	versioned segment tree, old versions stay queryable`pst.update(0,idx,val); pst.query(v2,l,r);`	O(log n)/ver	standard	PersistentSegmentTree.cpp
SG04	MergeSortTree	count-less-than / order-stat range queries, static`mst.countLess(l,r,x);`	O(log^2 n)	house	MergeSortTree.cpp
SG05	MaxSubarraySeg	max-subarray-sum segment tree, point-set`st.modify(pos,val); st.query(l,r);`	O(log n)	house	DynamicSubarraySum.cpp
SG06	RangeToggleSum	range XOR-toggle on a binary array + range sum`st.toggle(l,r); st.query(l,r);`	O(log n)	house	RangeToggleSum.cpp

06 FN

Fenwick trees

FenwickTree/ BIT and its range/2D extensions 4

call	trigger	what it does	cx	src	file
FN01	Fenwick	point-update range-sum BIT + binary search`f.update(i, v); f.query(l, r); f.lower_bound(v);`	O(log n)	house	FenwickTree.cpp
FN02	FenwickRUPQ	range-update point-query BIT`f.update(l, r, v); f.query(i);`	O(log n)	standard	FenwickRangeUpdatePointQuery.cpp
FN03	FenwickRURQ	range-update range-query BIT, two-BIT trick`f.update(l, r, v); f.query(l, r);`	O(log n)	standard	FenwickRangeUpdateRangeQuery.cpp
FN04	Fenwick2D	2D point-update rectangle-sum-query`f.update(x, y, v); f.query(x1, y1, x2, y2);`	O(log n log m)	standard	Fenwick2D.cpp

07 RM

RMQ

RMQ/ O(1)-query sparse tables, 1D and 2D 2

call	trigger	what it does	cx	src	file
RM01	SparseTable	O(1) RMQ, generic idempotent op (min/max/gcd)`st.query(l,r); // NOT sum`	O(1) qry	house	SparseTable.cpp
RM02	RMQ2D	2D range min/max query`st.query(x1,y1,x2,y2);`	O(1) qry	house	RMQ2D.cpp

08 DP

DP scaffolds

DP/ skeletons and classic transition optimizations 6

call	trigger	what it does	cx	src	file
DP01	DigitDP	digit-DP skeleton with a worked toy example`DigitDP dp(bound, K); int ans = dp.count();`	O(dig*states)	house	DigitDP.cpp
DP02	BitmaskDP	bitmask-DP skeleton, assignment-problem shape`BitmaskDP dp(cost); int best = dp.answer();`	O(2^n * n)	house	BitmaskDP.cpp
DP03	SOSDP	sum-over-subsets DP`vector<int> g = sos(f);`	O(n * 2^n)	cp-algo	SOSDP.cpp
DP04	DnCOpt	divide-and-conquer DP optimization`solveDnC(cur, prev, 1, n, 0, n - 1, cost); cur[0] is the base case, handle it yourself.`	O(n log n)~	KACTL	DivideAndConquerOpt.cpp
DP05	KnuthOpt	Knuth's DP optimization, quadrangle inequality`KnuthOpt opt(n, [&](int i, int j) { return ...; }); int best = opt.answer();`	O(n^2)	KACTL	KnuthOpt.cpp
DP06	CHT	convex hull trick, max/min line envelope`lc.add(k, m); lc.query(x);`	O(log n) qry	KACTL	ConvexHullTrick.cpp

09 MC

Misc

Others/ small single-purpose utilities 3

call	trigger	what it does	cx	src	file
MC01	MinStack	stack with running minimum`ms.push(5); ms.getMin();`	O(1)	house	MinStack.cpp
MC02	PrefixSuffixMex	prefix/suffix mex of an array`prefixSuffixMex(arr);`	O(n)	house	PrefixSuffixMex.cpp
MC03	TernarySearch	ternary search on a unimodal integer function`ternarySearchMin(lo,hi,f);`	O(log n)	house	TernarySearch.cpp
MC04	BalMultiset	multiset with lower median and sum of \|v - median\|`BalancedMultiset s: insert(x), erase(x) (x must be present), size(), median() = LOWER medi`	O(log n)	house	BalancedMultiset.cpp
MC05	MinDeque	O(1) queue with running minimum (sliding window)`MinDeque d (self-contained, two stacks): push_front/push_back(x), pop_front/pop_back(), fr`	O(1) amortised	house	MinStack_Mindeque.cpp
MC06	Trie	array trie: insert/erase, count words and prefixes`Trie t (lowercase a-z; change ALPHA/BASE for another alphabet): insert(s) (multiset: dupli`	O(len)	house	WordTrie.cpp
MC07	DivWindow	n/k minus max block frequency over divisor windows`minimumOperationsToMakeKPeriodic(word, k) (LeetCode 3137; k divides \|word\|): one operatio`	O(n)	house	divisor_window.cpp

file	what it does	file
.vimrc	the actual Vim config — cross-platform compiler resolution (`g++` on Linux, newest Homebrew `g++-N` on macOS), clipboard + `F7` compile/run mappings.`brew install gcc astyle # one-time, macOS only`	vimrc/vimrc
cpp.snippets	every template below, as an UltiSnips trigger. No comments by design — fast to read mid-contest.`normal<Tab> DSU<Tab> list<Tab>`	UltiSnips/cpp.snippets
INDEX.md	the human-readable lookup this whole page is generated from — every trigger, description and usage example. `list<Tab>` reads it live.`source of truth -- keep it updated when a snippet changes`	UltiSnips/INDEX.md
bash_aliases	`cstart [dir] name...` — creates `input.txt`/`output.txt` + empty `.cpp` under `$CSTART_DIR`, opens it in Vim.`cstart abcd a,b,c # contest abcd, opens a.cpp`	bash_aliases