Расширения декартова дерева: различия между версиями
Перейти к навигации
Перейти к поиску
Ctrlalt (обсуждение | вклад) Нет описания правки |
Ctrlalt (обсуждение | вклад) Нет описания правки |
||
(не показано 13 промежуточных версий этого же участника) | |||
Строка 1: | Строка 1: | ||
== TLDR == | |||
<youtube width="300" height="180">MLIbII4sBs0</youtube> | |||
<youtube width="300" height="180">mkpeHhmmUPw</youtube> | |||
== Multimap с getMinValue == | |||
{|width=100% | |||
|width=50%| | |||
'''getMinValue(lKey, rKey)''' | |||
class Treap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int key, priority, value, minValue; | |||
Node *left = 0, *right = 0; | |||
Node(int key, int value) : key(key), priority(gen()), value(value), minValue(value) {} | |||
} *root = 0; | |||
int getMinValue(Node *n) const { | |||
return n ? n->minValue : 2e9; | |||
} | |||
void update(Node *n) { | |||
if (n) | |||
n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int key, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (t->key < key) { | |||
split(t->right, key, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, key, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
public: | |||
void insert(int key, int value) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
root = merge(a, merge(new Node(key, value), b)); | |||
} | |||
void erase(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void eraseOne(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
if (b) | |||
b = merge(b->left, b->right); | |||
root = merge(a, merge(b, c)); | |||
} | |||
int getMinValue(int lKey, int rKey) { | |||
Node *a, *b, *c; | |||
split(root, lKey, a, b); | |||
split(b, rKey + 1, b, c); | |||
int res = getMinValue(b); | |||
root = merge(a, merge(b, c)); | |||
return res; | |||
} | |||
}; | |||
|width=50%| | |||
'''getMinValue(lIndex, rIndex)''' | |||
class Treap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int key, priority, size = 1, value, minValue; | |||
Node *left = 0, *right = 0; | |||
Node(int key, int value) : key(key), priority(gen()), value(value), minValue(value) {} | |||
} *root = 0; | |||
int getSize(Node *n) const { | |||
return n ? n->size : 0; | |||
} | |||
int getMinValue(Node *n) const { | |||
return n ? n->minValue : 2e9; | |||
} | |||
void update(Node *n) { | |||
if (n) { | |||
n->size = getSize(n->left) + 1 + getSize(n->right); | |||
n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); | |||
} | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int key, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (t->key < key) { | |||
split(t->right, key, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, key, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
void splitByIndex(Node *t, int index, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
int leftSize = getSize(t->left); | |||
if (leftSize < index) { | |||
splitByIndex(t->right, index - leftSize - 1, t->right, b); | |||
a = t; | |||
} else { | |||
splitByIndex(t->left, index, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
public: | |||
void insert(int key, int value) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
root = merge(a, merge(new Node(key, value), b)); | |||
} | |||
void erase(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void eraseOne(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
if (b) | |||
b = merge(b->left, b->right); | |||
root = merge(a, merge(b, c)); | |||
} | |||
int getMinValue(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
splitByIndex(root, lIndex, a, b); | |||
splitByIndex(b, rIndex - lIndex + 1, b, c); | |||
int res = getMinValue(b); | |||
root = merge(a, merge(b, c)); | |||
return res; | |||
} | |||
}; | |||
|} | |||
== Multiset с indexOf(key), operator[], lessCount(key), greaterCount(key) == | |||
{|width=100% | |||
|width=50%| | |||
'''Одинаковые элементы хранятся в нескольких узлах''' | |||
class Treap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int key, priority, size = 1; | |||
Node *left = 0, *right = 0; | |||
Node(int key) : key(key), priority(gen()) {} | |||
} *root = 0; | |||
int getSize(Node *n) const { | |||
return n ? n->size : 0; | |||
} | |||
void update(Node *n) { | |||
if (n) | |||
n->size = getSize(n->left) + 1 + getSize(n->right); | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int key, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (t->key < key) { | |||
split(t->right, key, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, key, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
int indexOf(Node *n, int key) const { | |||
if (!n) | |||
return 0; | |||
else if (key < n->key) | |||
return indexOf(n->left, key); | |||
else if (n->key == key) | |||
return getSize(n->left); | |||
else | |||
return getSize(n->left) + 1 + indexOf(n->right, key); | |||
} | |||
int getByIndex(Node *n, int index) const { | |||
int leftSize = getSize(n->left); | |||
if (leftSize > index) | |||
return getByIndex(n->left, index); | |||
else if (leftSize == index) | |||
return n->key; | |||
else | |||
return getByIndex(n->right, index - leftSize - 1); | |||
} | |||
public: | |||
int size() const { | |||
return getSize(root); | |||
} | |||
int indexOf(int key) const { | |||
return indexOf(root, key); | |||
} | |||
int operator[](int index) const { | |||
return getByIndex(root, index); | |||
} | |||
void insert(int key) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
root = merge(a, merge(new Node(key), b)); | |||
} | |||
void erase(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void eraseOne(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
if (b) | |||
b = merge(b->left, b->right); | |||
root = merge(a, merge(b, c)); | |||
} | |||
int lessCount(int key) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
int res = getSize(a); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int lessEqualCount(int key) { | |||
Node *a, *b; | |||
split(root, key + 1, a, b); | |||
int res = getSize(a); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int greaterCount(int key) { | |||
Node *a, *b; | |||
split(root, key + 1, a, b); | |||
int res = getSize(b); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int greaterEqualCount(int key) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
int res = getSize(b); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
}; | |||
|width=50%| | |||
'''Одинаковые элементы хранятся в одном узле''' | |||
class Treap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int key, priority, nodeSize = 1, subtreeSize = 1; | |||
Node *left = 0, *right = 0; | |||
Node(int key) : key(key), priority(gen()) {} | |||
} *root = 0; | |||
int getSubtreeSize(Node *n) const { | |||
return n ? n->subtreeSize : 0; | |||
} | |||
void update(Node *n) { | |||
if (n) | |||
n->subtreeSize = getSubtreeSize(n->left) + n->nodeSize + getSubtreeSize(n->right); | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int key, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (t->key < key) { | |||
split(t->right, key, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, key, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
int indexOf(Node *n, int key) const { | |||
if (!n) | |||
return 0; | |||
else if (key < n->key) | |||
return indexOf(n->left, key); | |||
else if (n->key == key) | |||
return getSubtreeSize(n->left); | |||
else | |||
return getSubtreeSize(n->left) + n->nodeSize + indexOf(n->right, key); | |||
} | |||
int getByIndex(Node *n, int index) const { | |||
int leftSize = getSubtreeSize(n->left); | |||
if (leftSize > index) | |||
return getByIndex(n->left, index); | |||
else if (leftSize + n->nodeSize >= index) | |||
return n->key; | |||
else | |||
return getByIndex(n->right, index - leftSize - n->nodeSize); | |||
} | |||
public: | |||
int size() const { | |||
return getSubtreeSize(root); | |||
} | |||
int indexOf(int key) const { | |||
return indexOf(root, key); | |||
} | |||
int operator[](int index) const { | |||
return getByIndex(root, index); | |||
} | |||
void insert(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
if (b) { | |||
b->nodeSize++; | |||
b->subtreeSize++; | |||
} else { | |||
b = new Node(key); | |||
} | |||
root = merge(a, merge(b, c)); | |||
} | |||
void erase(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void eraseOne(int key) { | |||
Node *a, *b, *c; | |||
split(root, key, a, b); | |||
split(b, key + 1, b, c); | |||
if (b) { | |||
b->nodeSize--; | |||
b->subtreeSize--; | |||
if (!b->nodeSize) | |||
b = 0; | |||
} | |||
root = merge(a, merge(b, c)); | |||
} | |||
int lessCount(int key) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
int res = getSize(a); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int lessEqualCount(int key) { | |||
Node *a, *b; | |||
split(root, key + 1, a, b); | |||
int res = getSize(a); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int greaterCount(int key) { | |||
Node *a, *b; | |||
split(root, key + 1, a, b); | |||
int res = getSize(b); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
int greaterEqualCount(int key) { | |||
Node *a, *b; | |||
split(root, key, a, b); | |||
int res = getSize(b); | |||
root = merge(a, b); | |||
return res; | |||
} | |||
}; | |||
|} | |||
== Set с find_by_order(index) и order_of_key(key) через __gnu_pbds == | |||
#include <ext/pb_ds/assoc_container.hpp> | |||
#include <ext/pb_ds/tree_policy.hpp> | |||
using namespace __gnu_pbds; | |||
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>; | |||
* [http://codeforces.com/contest/61/submission/61118877 Пример решения] | |||
* [https://codeforces.com/blog/entry/11080 Codeforces — C++ STL: Policy based data structures] | |||
== Vector == | |||
{|width=100% | |||
|width=50%| | |||
'''getMinValue(lIndex, rIndex)''' | |||
class ImplicitTreap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int value, priority, size = 1, minValue; | |||
Node *left = 0, *right = 0; | |||
Node(int value) : value(value), priority(gen()), minValue(value) {} | |||
} *root = 0; | |||
int getSize(Node *n) { | |||
return n ? n->size : 0; | |||
} | |||
int getMinValue(Node *n) { | |||
return n ? n->minValue : 2e9; | |||
} | |||
void update(Node *n) { | |||
if (n) { | |||
n->size = getSize(n->left) + 1 + getSize(n->right); | |||
n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); | |||
} | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int k, Node *&a, Node *&b) { | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (getSize(t->left) < k) { | |||
split(t->right, k - getSize(t->left) - 1, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, k, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
public: | |||
void pushBack(int value) { | |||
root = merge(root, new Node(value)); | |||
} | |||
void pushFront(int value) { | |||
root = merge(new Node(value), root); | |||
} | |||
void insertAfter(int index, int value) { | |||
Node *a, *b; | |||
split(root, index, a, b); | |||
root = merge(a, merge(new Node(value), b)); | |||
} | |||
void erase(int index) { | |||
Node *a, *b, *c; | |||
split(root, index, a, b); | |||
split(b, 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void erase(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
int operator[](int index) { | |||
Node *a, *b, *c; | |||
split(root, index, a, b); | |||
split(b, 1, b, c); | |||
int res = b->value; | |||
root = merge(a, merge(b, c)); | |||
return res; | |||
} | |||
void moveToFront(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(b, merge(a, c)); | |||
} | |||
void moveToBack(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(a, merge(c, b)); | |||
} | |||
int getMinValue(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
int res = getMinValue(b); | |||
root = merge(a, merge(b, c)); | |||
return res; | |||
} | |||
}; | |||
|width=50%| | |||
'''reverse(lIndex, rIndex)''' | |||
class ImplicitTreap { | |||
inline static minstd_rand gen; | |||
struct Node { | |||
int value, priority, size = 1, rev = 0; | |||
Node *left = 0, *right = 0; | |||
Node(int value) : value(value), priority(gen()) {} | |||
} *root = 0; | |||
int getSize(Node *n) { | |||
return n ? n->size : 0; | |||
} | |||
void push(Node *n) { | |||
if (n && n->rev) { | |||
swap(n->left, n->right); | |||
if (n->left) | |||
n->left->rev ^= 1; | |||
if (n->right) | |||
n->right->rev ^= 1; | |||
n->rev = 0; | |||
} | |||
} | |||
void update(Node *n) { | |||
if (n) | |||
n->size = getSize(n->left) + 1 + getSize(n->right); | |||
} | |||
Node *merge(Node *a, Node *b) { | |||
push(a); | |||
push(b); | |||
if (!a || !b) | |||
return a ? a : b; | |||
if (a->priority > b->priority) { | |||
a->right = merge(a->right, b); | |||
update(a); | |||
return a; | |||
} else { | |||
b->left = merge(a, b->left); | |||
update(b); | |||
return b; | |||
} | |||
} | |||
void split(Node *t, int k, Node *&a, Node *&b) { | |||
push(t); | |||
if (!t) { | |||
a = b = 0; | |||
return; | |||
} | |||
if (getSize(t->left) < k) { | |||
split(t->right, k - getSize(t->left) - 1, t->right, b); | |||
a = t; | |||
} else { | |||
split(t->left, k, a, t->left); | |||
b = t; | |||
} | |||
update(a); | |||
update(b); | |||
} | |||
public: | |||
void pushBack(int value) { | |||
root = merge(root, new Node(value)); | |||
} | |||
void pushFront(int value) { | |||
root = merge(new Node(value), root); | |||
} | |||
void insertAfter(int index, int value) { | |||
Node *a, *b; | |||
split(root, index, a, b); | |||
root = merge(a, merge(new Node(value), b)); | |||
} | |||
void erase(int index) { | |||
Node *a, *b, *c; | |||
split(root, index, a, b); | |||
split(b, 1, b, c); | |||
root = merge(a, c); | |||
} | |||
void erase(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(a, c); | |||
} | |||
int operator[](int index) { | |||
Node *a, *b, *c; | |||
split(root, index, a, b); | |||
split(b, 1, b, c); | |||
int res = b->value; | |||
root = merge(a, merge(b, c)); | |||
return res; | |||
} | |||
void moveToFront(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(b, merge(a, c)); | |||
} | |||
void moveToBack(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
root = merge(a, merge(c, b)); | |||
} | |||
void reverse(int lIndex, int rIndex) { | |||
Node *a, *b, *c; | |||
split(root, lIndex, a, b); | |||
split(b, rIndex - lIndex + 1, b, c); | |||
b->rev = 1; | |||
root = merge(a, merge(b, c)); | |||
} | |||
}; | |||
|} | |||
== Ссылки == | == Ссылки == | ||
Теория: | |||
* [https://www.youtube.com/watch?v=MLIbII4sBs0&list=PLGhUJWLZ8uQ5Ewplzb1ER29p4-kQme5Yr&index=5 Фолунин В. — Декартово дерево по неявному ключу] | |||
* [http://e-maxx.ru/algo/treap#7 e-maxx.ru — Неявные декартовы деревья] | * [http://e-maxx.ru/algo/treap#7 e-maxx.ru — Неявные декартовы деревья] | ||
* [http://neerc.ifmo.ru/wiki/index.php?title=%D0%94%D0%B5%D0%BA%D0%B0%D1%80%D1%82%D0%BE%D0%B2%D0%BE_%D0%B4%D0%B5%D1%80%D0%B5%D0%B2%D0%BE_%D0%BF%D0%BE_%D0%BD%D0%B5%D1%8F%D0%B2%D0%BD%D0%BE%D0%BC%D1%83_%D0%BA%D0%BB%D1%8E%D1%87%D1%83 neerc.ifmo.ru/wiki — Декартово дерево по неявному ключу] | * [http://neerc.ifmo.ru/wiki/index.php?title=%D0%94%D0%B5%D0%BA%D0%B0%D1%80%D1%82%D0%BE%D0%B2%D0%BE_%D0%B4%D0%B5%D1%80%D0%B5%D0%B2%D0%BE_%D0%BF%D0%BE_%D0%BD%D0%B5%D1%8F%D0%B2%D0%BD%D0%BE%D0%BC%D1%83_%D0%BA%D0%BB%D1%8E%D1%87%D1%83 neerc.ifmo.ru/wiki — Декартово дерево по неявному ключу] | ||
* [http://habrahabr.ru/post/102364/ habrahabr.ru — Декартово дерево: Часть 3. Декартово дерево по неявному ключу] | * [http://habrahabr.ru/post/102364/ habrahabr.ru — Декартово дерево: Часть 3. Декартово дерево по неявному ключу] | ||
* [http://opentrains.mipt.ru/zksh/files/zksh2015/lectures/zksh_cartesian.pdf Иващенко Д., Семенов К. Декартово дерево] | |||
Код: | |||
* [https://github.com/indy256/codelibrary/blob/master/cpp/structures/treap_indexed.cpp github.com/indy256/codelibrary/blob/master/cpp/structures/treap_indexed.cpp] | |||
* [http://github.com/ADJA/algos/blob/master/DataStructures/CartesianTreeImplicitKeys.cpp Algos — Cartesian tree using implicit keys] | |||
Задачи: | |||
* [http://informatics.mccme.ru/course/view.php?id=18 informatics.mccme.ru — Курс «Структуры данных» — часть 4] | * [http://informatics.mccme.ru/course/view.php?id=18 informatics.mccme.ru — Курс «Структуры данных» — часть 4] | ||
* [ | * [[:Категория:Задачи: Декартово дерево по неявному ключу|Задачи: Декартово дерево по неявному ключу]] | ||
* [[:Категория:Задачи: Дерево Корнеева|Задачи: Дерево Корнеева]] | |||
[[Category:Балансирующиеся деревья]] | [[Category:Балансирующиеся деревья]] |
Текущая версия от 15:09, 24 мая 2023
TLDR
Multimap с getMinValue
getMinValue(lKey, rKey) class Treap { inline static minstd_rand gen; struct Node { int key, priority, value, minValue; Node *left = 0, *right = 0; Node(int key, int value) : key(key), priority(gen()), value(value), minValue(value) {} } *root = 0; int getMinValue(Node *n) const { return n ? n->minValue : 2e9; } void update(Node *n) { if (n) n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); } Node *merge(Node *a, Node *b) { if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int key, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } if (t->key < key) { split(t->right, key, t->right, b); a = t; } else { split(t->left, key, a, t->left); b = t; } update(a); update(b); } public: void insert(int key, int value) { Node *a, *b; split(root, key, a, b); root = merge(a, merge(new Node(key, value), b)); } void erase(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); root = merge(a, c); } void eraseOne(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); if (b) b = merge(b->left, b->right); root = merge(a, merge(b, c)); } int getMinValue(int lKey, int rKey) { Node *a, *b, *c; split(root, lKey, a, b); split(b, rKey + 1, b, c); int res = getMinValue(b); root = merge(a, merge(b, c)); return res; } }; |
getMinValue(lIndex, rIndex) class Treap { inline static minstd_rand gen; struct Node { int key, priority, size = 1, value, minValue; Node *left = 0, *right = 0; Node(int key, int value) : key(key), priority(gen()), value(value), minValue(value) {} } *root = 0; int getSize(Node *n) const { return n ? n->size : 0; } int getMinValue(Node *n) const { return n ? n->minValue : 2e9; } void update(Node *n) { if (n) { n->size = getSize(n->left) + 1 + getSize(n->right); n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); } } Node *merge(Node *a, Node *b) { if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int key, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } if (t->key < key) { split(t->right, key, t->right, b); a = t; } else { split(t->left, key, a, t->left); b = t; } update(a); update(b); } void splitByIndex(Node *t, int index, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } int leftSize = getSize(t->left); if (leftSize < index) { splitByIndex(t->right, index - leftSize - 1, t->right, b); a = t; } else { splitByIndex(t->left, index, a, t->left); b = t; } update(a); update(b); } public: void insert(int key, int value) { Node *a, *b; split(root, key, a, b); root = merge(a, merge(new Node(key, value), b)); } void erase(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); root = merge(a, c); } void eraseOne(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); if (b) b = merge(b->left, b->right); root = merge(a, merge(b, c)); } int getMinValue(int lIndex, int rIndex) { Node *a, *b, *c; splitByIndex(root, lIndex, a, b); splitByIndex(b, rIndex - lIndex + 1, b, c); int res = getMinValue(b); root = merge(a, merge(b, c)); return res; } }; |
Multiset с indexOf(key), operator[], lessCount(key), greaterCount(key)
Одинаковые элементы хранятся в нескольких узлах class Treap { inline static minstd_rand gen; struct Node { int key, priority, size = 1; Node *left = 0, *right = 0; Node(int key) : key(key), priority(gen()) {} } *root = 0; int getSize(Node *n) const { return n ? n->size : 0; } void update(Node *n) { if (n) n->size = getSize(n->left) + 1 + getSize(n->right); } Node *merge(Node *a, Node *b) { if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int key, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } if (t->key < key) { split(t->right, key, t->right, b); a = t; } else { split(t->left, key, a, t->left); b = t; } update(a); update(b); } int indexOf(Node *n, int key) const { if (!n) return 0; else if (key < n->key) return indexOf(n->left, key); else if (n->key == key) return getSize(n->left); else return getSize(n->left) + 1 + indexOf(n->right, key); } int getByIndex(Node *n, int index) const { int leftSize = getSize(n->left); if (leftSize > index) return getByIndex(n->left, index); else if (leftSize == index) return n->key; else return getByIndex(n->right, index - leftSize - 1); } public: int size() const { return getSize(root); } int indexOf(int key) const { return indexOf(root, key); } int operator[](int index) const { return getByIndex(root, index); } void insert(int key) { Node *a, *b; split(root, key, a, b); root = merge(a, merge(new Node(key), b)); } void erase(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); root = merge(a, c); } void eraseOne(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); if (b) b = merge(b->left, b->right); root = merge(a, merge(b, c)); } int lessCount(int key) { Node *a, *b; split(root, key, a, b); int res = getSize(a); root = merge(a, b); return res; } int lessEqualCount(int key) { Node *a, *b; split(root, key + 1, a, b); int res = getSize(a); root = merge(a, b); return res; } int greaterCount(int key) { Node *a, *b; split(root, key + 1, a, b); int res = getSize(b); root = merge(a, b); return res; } int greaterEqualCount(int key) { Node *a, *b; split(root, key, a, b); int res = getSize(b); root = merge(a, b); return res; } }; |
Одинаковые элементы хранятся в одном узле class Treap { inline static minstd_rand gen; struct Node { int key, priority, nodeSize = 1, subtreeSize = 1; Node *left = 0, *right = 0; Node(int key) : key(key), priority(gen()) {} } *root = 0; int getSubtreeSize(Node *n) const { return n ? n->subtreeSize : 0; } void update(Node *n) { if (n) n->subtreeSize = getSubtreeSize(n->left) + n->nodeSize + getSubtreeSize(n->right); } Node *merge(Node *a, Node *b) { if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int key, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } if (t->key < key) { split(t->right, key, t->right, b); a = t; } else { split(t->left, key, a, t->left); b = t; } update(a); update(b); } int indexOf(Node *n, int key) const { if (!n) return 0; else if (key < n->key) return indexOf(n->left, key); else if (n->key == key) return getSubtreeSize(n->left); else return getSubtreeSize(n->left) + n->nodeSize + indexOf(n->right, key); } int getByIndex(Node *n, int index) const { int leftSize = getSubtreeSize(n->left); if (leftSize > index) return getByIndex(n->left, index); else if (leftSize + n->nodeSize >= index) return n->key; else return getByIndex(n->right, index - leftSize - n->nodeSize); } public: int size() const { return getSubtreeSize(root); } int indexOf(int key) const { return indexOf(root, key); } int operator[](int index) const { return getByIndex(root, index); } void insert(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); if (b) { b->nodeSize++; b->subtreeSize++; } else { b = new Node(key); } root = merge(a, merge(b, c)); } void erase(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); root = merge(a, c); } void eraseOne(int key) { Node *a, *b, *c; split(root, key, a, b); split(b, key + 1, b, c); if (b) { b->nodeSize--; b->subtreeSize--; if (!b->nodeSize) b = 0; } root = merge(a, merge(b, c)); } int lessCount(int key) { Node *a, *b; split(root, key, a, b); int res = getSize(a); root = merge(a, b); return res; } int lessEqualCount(int key) { Node *a, *b; split(root, key + 1, a, b); int res = getSize(a); root = merge(a, b); return res; } int greaterCount(int key) { Node *a, *b; split(root, key + 1, a, b); int res = getSize(b); root = merge(a, b); return res; } int greaterEqualCount(int key) { Node *a, *b; split(root, key, a, b); int res = getSize(b); root = merge(a, b); return res; } }; |
Set с find_by_order(index) и order_of_key(key) через __gnu_pbds
#include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace __gnu_pbds; using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
Vector
getMinValue(lIndex, rIndex) class ImplicitTreap { inline static minstd_rand gen; struct Node { int value, priority, size = 1, minValue; Node *left = 0, *right = 0; Node(int value) : value(value), priority(gen()), minValue(value) {} } *root = 0; int getSize(Node *n) { return n ? n->size : 0; } int getMinValue(Node *n) { return n ? n->minValue : 2e9; } void update(Node *n) { if (n) { n->size = getSize(n->left) + 1 + getSize(n->right); n->minValue = min({ getMinValue(n->left), n->value, getMinValue(n->right) }); } } Node *merge(Node *a, Node *b) { if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int k, Node *&a, Node *&b) { if (!t) { a = b = 0; return; } if (getSize(t->left) < k) { split(t->right, k - getSize(t->left) - 1, t->right, b); a = t; } else { split(t->left, k, a, t->left); b = t; } update(a); update(b); } public: void pushBack(int value) { root = merge(root, new Node(value)); } void pushFront(int value) { root = merge(new Node(value), root); } void insertAfter(int index, int value) { Node *a, *b; split(root, index, a, b); root = merge(a, merge(new Node(value), b)); } void erase(int index) { Node *a, *b, *c; split(root, index, a, b); split(b, 1, b, c); root = merge(a, c); } void erase(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(a, c); } int operator[](int index) { Node *a, *b, *c; split(root, index, a, b); split(b, 1, b, c); int res = b->value; root = merge(a, merge(b, c)); return res; } void moveToFront(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(b, merge(a, c)); } void moveToBack(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(a, merge(c, b)); } int getMinValue(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); int res = getMinValue(b); root = merge(a, merge(b, c)); return res; } }; |
reverse(lIndex, rIndex) class ImplicitTreap { inline static minstd_rand gen; struct Node { int value, priority, size = 1, rev = 0; Node *left = 0, *right = 0; Node(int value) : value(value), priority(gen()) {} } *root = 0; int getSize(Node *n) { return n ? n->size : 0; } void push(Node *n) { if (n && n->rev) { swap(n->left, n->right); if (n->left) n->left->rev ^= 1; if (n->right) n->right->rev ^= 1; n->rev = 0; } } void update(Node *n) { if (n) n->size = getSize(n->left) + 1 + getSize(n->right); } Node *merge(Node *a, Node *b) { push(a); push(b); if (!a || !b) return a ? a : b; if (a->priority > b->priority) { a->right = merge(a->right, b); update(a); return a; } else { b->left = merge(a, b->left); update(b); return b; } } void split(Node *t, int k, Node *&a, Node *&b) { push(t); if (!t) { a = b = 0; return; } if (getSize(t->left) < k) { split(t->right, k - getSize(t->left) - 1, t->right, b); a = t; } else { split(t->left, k, a, t->left); b = t; } update(a); update(b); } public: void pushBack(int value) { root = merge(root, new Node(value)); } void pushFront(int value) { root = merge(new Node(value), root); } void insertAfter(int index, int value) { Node *a, *b; split(root, index, a, b); root = merge(a, merge(new Node(value), b)); } void erase(int index) { Node *a, *b, *c; split(root, index, a, b); split(b, 1, b, c); root = merge(a, c); } void erase(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(a, c); } int operator[](int index) { Node *a, *b, *c; split(root, index, a, b); split(b, 1, b, c); int res = b->value; root = merge(a, merge(b, c)); return res; } void moveToFront(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(b, merge(a, c)); } void moveToBack(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); root = merge(a, merge(c, b)); } void reverse(int lIndex, int rIndex) { Node *a, *b, *c; split(root, lIndex, a, b); split(b, rIndex - lIndex + 1, b, c); b->rev = 1; root = merge(a, merge(b, c)); } }; |
Ссылки
Теория:
- Фолунин В. — Декартово дерево по неявному ключу
- e-maxx.ru — Неявные декартовы деревья
- neerc.ifmo.ru/wiki — Декартово дерево по неявному ключу
- habrahabr.ru — Декартово дерево: Часть 3. Декартово дерево по неявному ключу
- Иващенко Д., Семенов К. Декартово дерево
Код:
- github.com/indy256/codelibrary/blob/master/cpp/structures/treap_indexed.cpp
- Algos — Cartesian tree using implicit keys
Задачи: