This documentation is automatically generated by online-judge-tools/verification-helper
#include "structure/lct/link-cut-tree.hpp"
Link Cut Tree とは動的木の一つで, 辺の追加や削除などの木構造の動的な変化がある場合でも効率的にクエリを処理できる.
LinkCutTree(f, s)
: コンストラクタ. f
は 2 つの要素の値をマージする二項演算, s
は要素を反転する演算を指す.alloc(v)
: 要素の値を v
としたノードを生成する.build(vs)
: 各要素の値を vs[i]
としたノードを生成し, その配列を返す.expose(t)
: t
と根をつなげて, t
を splay Tree の根にする.evert(t)
: t
を根に変更する.link(child, parent)
: child
の親を parent
にする. child
と parent
は別の連結成分で, child
が根であることを要求する.cut(child)
: child
の親と child
を切り離す.is_connected(u, v)
: u
と v
が同じ連結成分に属する場合は true
, そうでなければ false
を返す.lca(u, v)
: u
と v
の lca を返す. u
と v
が異なる連結成分なら nullptr
を返す.get_kth(x, k)
: x
から根までのパスに出現するノードを並べたとき, 0-indexed で k
番目のノードを返す.query(u)
: u
から根までのパス上の頂点の値を二項演算でまとめた結果を返す.query(u, v)
: u
から v
までのパス上の頂点の値を二項演算でまとめた結果を返す.set_key(t, v)
: t
の値を v
に変更する./**
* @brief Link Cut Tree
*
*/
template< typename T, typename F, typename S >
struct LinkCutTree {
private:
F f;
S s;
struct Node {
Node *l, *r, *p;
T key, sum;
bool rev;
size_t sz;
explicit Node(const T &v) : key(v), sum(v), sz(1), rev(false),
l(nullptr), r(nullptr), p(nullptr) {}
bool is_root() const {
return not p or (p->l != this and p->r != this);
}
};
public:
using NP = Node *;
private:
NP update(NP t) {
t->sz = 1;
t->sum = t->key;
if(t->l) t->sz += t->l->sz, t->sum = f(t->l->sum, t->sum);
if(t->r) t->sz += t->r->sz, t->sum = f(t->sum, t->r->sum);
return t;
}
void rotr(NP t) {
NP x = t->p, y = x->p;
if((x->l = t->r)) t->r->p = x;
t->r = x, x->p = t;
update(x), update(t);
if((t->p = y)) {
if(y->l == x) y->l = t;
if(y->r == x) y->r = t;
update(y);
}
}
void rotl(NP t) {
NP x = t->p, y = x->p;
if((x->r = t->l)) t->l->p = x;
t->l = x, x->p = t;
update(x), update(t);
if((t->p = y)) {
if(y->l == x) y->l = t;
if(y->r == x) y->r = t;
update(y);
}
}
void toggle(NP t) {
swap(t->l, t->r);
t->sum = s(t->sum);
t->rev ^= true;
}
void push(NP t) {
if(t->rev) {
if(t->l) toggle(t->l);
if(t->r) toggle(t->r);
t->rev = false;
}
}
void splay(NP t) {
push(t);
while(not t->is_root()) {
NP q = t->p;
if(q->is_root()) {
push(q), push(t);
if(q->l == t) rotr(t);
else rotl(t);
} else {
NP r = q->p;
push(r), push(q), push(t);
if(r->l == q) {
if(q->l == t) rotr(q), rotr(t);
else rotl(t), rotr(t);
} else {
if(q->r == t) rotl(q), rotl(t);
else rotr(t), rotl(t);
}
}
}
}
public:
LinkCutTree(const F &f, const S &s) : f(f), s(s) {}
NP alloc(const T &v = T()) {
return new Node(v);
}
vector< NP > build(vector< T > &vs) {
vector< NP > nodes(vs.size());
for(int i = 0; i < (int) vs.size(); i++) {
nodes[i] = alloc(vs[i]);
}
return nodes;
}
NP expose(NP t) {
NP rp = nullptr;
for(NP cur = t; cur; cur = cur->p) {
splay(cur);
cur->r = rp;
update(cur);
rp = cur;
}
splay(t);
return rp;
}
void evert(NP t) {
expose(t);
toggle(t);
push(t);
}
void link(NP child, NP parent) {
if(is_connected(child, parent)) {
throw runtime_error("child and parent must be different connected components");
}
if(child->l) {
throw runtime_error("child must be root");
}
child->p = parent;
parent->r = child;
update(parent);
}
void cut(NP child) {
expose(child);
NP parent = child->l;
if(not parent) {
throw runtime_error("child must not be root");
}
child->l = nullptr;
parent->p = nullptr;
update(child);
}
bool is_connected(NP u, NP v) {
expose(u), expose(v);
return u == v or u->p;
}
NP lca(NP u, NP v) {
if(not is_connected(u, v)) return nullptr;
expose(u);
return expose(v);
}
NP get_kth(NP x, int k) {
expose(x);
while(x) {
push(x);
if(x->r && x->r->sz > k) {
x = x->r;
} else {
if(x->r) k -= x->r->sz;
if(k == 0) {
splay(x);
return x;
}
k -= 1;
x = x->l;
}
}
return nullptr;
}
const T &query(NP u) {
expose(u);
return u->sum;
}
const T &query(NP u, NP v) {
evert(u);
return query(v);
}
void set_key(NP t, T v) {
expose(t);
t->key = v;
update(t);
}
};
template< typename T, typename F, typename S >
LinkCutTree< T, F, S > get_link_cut_tree(const F &f, const S &s) {
return {f, s};
}
#line 1 "structure/lct/link-cut-tree.hpp"
/**
* @brief Link Cut Tree
*
*/
template< typename T, typename F, typename S >
struct LinkCutTree {
private:
F f;
S s;
struct Node {
Node *l, *r, *p;
T key, sum;
bool rev;
size_t sz;
explicit Node(const T &v) : key(v), sum(v), sz(1), rev(false),
l(nullptr), r(nullptr), p(nullptr) {}
bool is_root() const {
return not p or (p->l != this and p->r != this);
}
};
public:
using NP = Node *;
private:
NP update(NP t) {
t->sz = 1;
t->sum = t->key;
if(t->l) t->sz += t->l->sz, t->sum = f(t->l->sum, t->sum);
if(t->r) t->sz += t->r->sz, t->sum = f(t->sum, t->r->sum);
return t;
}
void rotr(NP t) {
NP x = t->p, y = x->p;
if((x->l = t->r)) t->r->p = x;
t->r = x, x->p = t;
update(x), update(t);
if((t->p = y)) {
if(y->l == x) y->l = t;
if(y->r == x) y->r = t;
update(y);
}
}
void rotl(NP t) {
NP x = t->p, y = x->p;
if((x->r = t->l)) t->l->p = x;
t->l = x, x->p = t;
update(x), update(t);
if((t->p = y)) {
if(y->l == x) y->l = t;
if(y->r == x) y->r = t;
update(y);
}
}
void toggle(NP t) {
swap(t->l, t->r);
t->sum = s(t->sum);
t->rev ^= true;
}
void push(NP t) {
if(t->rev) {
if(t->l) toggle(t->l);
if(t->r) toggle(t->r);
t->rev = false;
}
}
void splay(NP t) {
push(t);
while(not t->is_root()) {
NP q = t->p;
if(q->is_root()) {
push(q), push(t);
if(q->l == t) rotr(t);
else rotl(t);
} else {
NP r = q->p;
push(r), push(q), push(t);
if(r->l == q) {
if(q->l == t) rotr(q), rotr(t);
else rotl(t), rotr(t);
} else {
if(q->r == t) rotl(q), rotl(t);
else rotr(t), rotl(t);
}
}
}
}
public:
LinkCutTree(const F &f, const S &s) : f(f), s(s) {}
NP alloc(const T &v = T()) {
return new Node(v);
}
vector< NP > build(vector< T > &vs) {
vector< NP > nodes(vs.size());
for(int i = 0; i < (int) vs.size(); i++) {
nodes[i] = alloc(vs[i]);
}
return nodes;
}
NP expose(NP t) {
NP rp = nullptr;
for(NP cur = t; cur; cur = cur->p) {
splay(cur);
cur->r = rp;
update(cur);
rp = cur;
}
splay(t);
return rp;
}
void evert(NP t) {
expose(t);
toggle(t);
push(t);
}
void link(NP child, NP parent) {
if(is_connected(child, parent)) {
throw runtime_error("child and parent must be different connected components");
}
if(child->l) {
throw runtime_error("child must be root");
}
child->p = parent;
parent->r = child;
update(parent);
}
void cut(NP child) {
expose(child);
NP parent = child->l;
if(not parent) {
throw runtime_error("child must not be root");
}
child->l = nullptr;
parent->p = nullptr;
update(child);
}
bool is_connected(NP u, NP v) {
expose(u), expose(v);
return u == v or u->p;
}
NP lca(NP u, NP v) {
if(not is_connected(u, v)) return nullptr;
expose(u);
return expose(v);
}
NP get_kth(NP x, int k) {
expose(x);
while(x) {
push(x);
if(x->r && x->r->sz > k) {
x = x->r;
} else {
if(x->r) k -= x->r->sz;
if(k == 0) {
splay(x);
return x;
}
k -= 1;
x = x->l;
}
}
return nullptr;
}
const T &query(NP u) {
expose(u);
return u->sum;
}
const T &query(NP u, NP v) {
evert(u);
return query(v);
}
void set_key(NP t, T v) {
expose(t);
t->key = v;
update(t);
}
};
template< typename T, typename F, typename S >
LinkCutTree< T, F, S > get_link_cut_tree(const F &f, const S &s) {
return {f, s};
}