C++:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 | #pragma once #include <cmath> #include <algorithm> #include <stack> namespace mds { template< typename T, typename Func = std::less<T> > class avl_tree { struct Node { T key; int h; Node *left; Node *right; }; Node *nil; Node *root; Func cmp; std::size_t len; template<typename ChildA, typename ChildB> Node* rotate(Node* n, ChildA childA, ChildB childB) { auto new_root = childA(n); childA(n) = childB(new_root); childB(new_root) = n; n->h = compute_h(n); new_root->h = compute_h(new_root); return new_root; } void destroy_tree(Node *n) { if (n == nil) { return; } destroy_tree(n->left); destroy_tree(n->right); delete n; } template<typename ChildA, typename ChildB> Node* tri_node_rotate(Node* x, ChildA childA, ChildB childB) { auto c = childA(x); if (childA(c)->h < childB(c)->h) { childA(x) = rotate(c, childB, childA); } return rotate(x, childA, childB); } Node* restructure(Node *n) { if (n->left->h > n->right->h) { return tri_node_rotate(n, left, right); } return tri_node_rotate(n, right, left); } void maintain_invariant(Node *&n) { n->h = compute_h(n); if (un_balance(n)) { n = restructure(n); } } int compute_h(const Node* n) const { return 1 + std::max(n->left->h, n->right->h); } bool un_balance(const Node *x) const { return std::abs(x->left->h - x->right->h) > 1; } template<typename TT> void insert_recursive(Node*& n, TT& key) { if (n == nil) { n = new Node{ std::forward<TT>(key),0, nil, nil }; ++len; } else if (cmp(key, n->key)) { insert_recursive(n->left, key); } else if (cmp(n->key, key)) { insert_recursive(n->right, key); } maintain_invariant(n); } void remove(Node *&n, const T& key) { if (n == nil) { return; } if (cmp(n->key, key)) { remove(n->right, key); } else if (cmp(key, n->key)) { remove(n->left, key); } else if (remove_node(n)) { --len; return; } maintain_invariant(n); } bool remove_node(Node *&n) { auto removed = n; if (n->left == nil) { n = n->right; } else if (n->right == nil) { n = n->left; } else { auto m = min(n->right); n->key = m->key; remove(n->right, m->key); return false; } delete removed; return true; } Node* min(Node *n) const { if (n->left == nil) { return n; } return min(n->left); } static Node*& left(Node* n) { return n->left; } static Node*& right(Node* n) { return n->right; } template<typename Func> void in_order_recursive(Node* n, Func func) const { if (n == nil) { return; } in_order_recursive(n->left, func); func(n->key); in_order_recursive(n->right, func); } public: avl_tree(Func pcmp) : nil(new Node{ T(), -1, nullptr, nullptr }), root(nil), cmp(pcmp) { } avl_tree() : avl_tree(Func()) { } avl_tree(std::initializer_list<T> list) : avl_tree(Func()) { for (auto e : list) { insert(e); } } ~avl_tree() { destroy_tree(root); delete nil; } void insert(const T& key) { insert_recursive(root, key); } void insert(T&& key) { insert_recursive(root, std::move(key)); } template<typename... Args> void emplace(Args&&... args) { insert_recursive(root, T(std::forward<Args>(args)...)); } template <typename Func> void walk(Func func) const { in_order_recursive(root, func); } void remove(const T &key) { remove(root, key); } std::size_t size() const { return len; } bool contains(const T& key) const { auto n = root; while (n != nil) { if (cmp(n->key, key)) { n = n->right; } else if (cmp(key, n->key)) { n = n->left; } else { return true; } } return false; } class TreeIterator : public std::iterator<std::forward_iterator_tag, std::remove_cv_t<T>, std::ptrdiff_t, const T*, const T&> { using node = Node*; node itr; node nil; std::stack<node> path; node find_successor(node n) { n = n->right; if (n != nil) { while (n->left != nil) { path.push(n); n = n->left; } } else { n = path.top(); path.pop(); } return n; } public: explicit TreeIterator(node n, node pnil) : nil(pnil) //begin { if (n == nil) itr = nil; else { path.push(nil); while (n->left != nil) { path.push(n); n = n->left; } itr = n; } } explicit TreeIterator(node pnil) // end : itr(pnil), nil(pnil) { } TreeIterator& operator++ () { itr = find_successor(itr); return *this; } TreeIterator operator++ (int) { TreeIterator tmp(*this); itr = find_successor(itr); return tmp; } bool operator == (const TreeIterator& rhs) const { return itr == rhs.itr; } bool operator != (const TreeIterator& rhs) const { return itr != rhs.itr; } const T& operator* () const { return itr->key; } const T& operator-> () const { return itr->key; } }; using const_iterator = TreeIterator; const_iterator begin() const { return const_iterator(root, nil); } const_iterator end() const { return const_iterator(nil); } }; } |
Rust:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 | pub mod set { use ::std::cmp; use ::std::cmp::Ordering::{Less, Greater, Equal}; use ::std::mem; pub struct AvlTree<T : Ord> { root : Option<Box<Node<T>>> } struct Node<T : Ord> { key : T, height : i32, left : AvlTree<T>, right : AvlTree<T>, } impl<T> Node<T> where T : Ord{ fn new(key: T) -> Option<Box<Node<T>>>{ Some(Box::new( Node { key : key, height : 0, left : AvlTree::new(), right : AvlTree::new() } )) } } impl<T> AvlTree<T> where T : Ord{ pub fn new() -> AvlTree<T> { AvlTree { root: None } } fn rotate<CA, CB>(&mut self, ch_a: &CA, ch_b: &CB) where CA: Fn(&mut Box<Node<T>>) -> &mut AvlTree<T>, CB: Fn(&mut Box<Node<T>>) -> &mut AvlTree<T> { let mut root = self.node_take(); let mut child = ch_a(&mut root).node_take(); ch_a(&mut root).root = ch_b(&mut child).root.take(); ch_b(&mut child).root = Some(root); ch_b(&mut child).update_height(); self.root = Some(child); self.update_height(); } fn double_rotate<CA, CB>(&mut self, ch_a: &CA, ch_b: &CB) where CA: Fn(&mut Box<Node<T>>) -> &mut AvlTree<T>, CB: Fn(&mut Box<Node<T>>) -> &mut AvlTree<T> { { let child = ch_b(self.m_box()); if ch_b(child.m_box()).h() < ch_a(child.m_box()).h() { child.rotate(ch_a, ch_b); } } self.rotate(ch_b, ch_a); } fn restructure(& mut self) { self.update_height(); let ord = self.root.as_ref() .map(|_| self.degree()) .map(|d| (d, d.cmp(&0))); match ord { Some((d, Less)) if -1 > d => { self.double_rotate( &|x| &mut x.left, &|x| &mut x.right) }, Some((d, Greater)) if d > 1 => { self.double_rotate( &|x| &mut x.right, &|x| &mut x.left) }, _ => { }, } } fn update_height(&mut self) { self.root.as_mut() .map(|r| r.height = cmp::max(r.right.h(), r.left.h()) + 1); } fn m_box(&mut self) -> &mut Box<Node<T>> { self.root.as_mut().expect("root can't be None") } fn r_box(&self) -> & Box<Node<T>> { self.root.as_ref().expect("root can't be None") } fn node_take(&mut self) -> Box<Node<T>> { self.root.take().expect("root can't be None") } fn h(&self) -> i32 { self.root.as_ref().map_or(-1, |x| x.height) } fn degree(&self) -> i32 { self.root .as_ref() .map(|x| x.left.h() - x.right.h()) .unwrap_or(0) } pub fn insert(&mut self, key : T) { match self.map_to_ord(&key) { Some(Less) => self.m_box().left.insert(key), Some(Greater) => self.m_box().right.insert(key), None => self.root = Node::new(key), _ => return, } self.restructure(); } pub fn remove(&mut self, key: &T) { match self.map_to_ord(key) { Some(Less) => self.m_box().left.remove(key), Some(Greater) => self.m_box().right.remove(key), Some(Equal) => self.remove_self(key), None => return, }; self.restructure(); } fn min(&mut self) -> &mut Box<Node<T>> { let n = self.m_box(); if n.left.root.is_none(){ return n; } n.left.min() } fn map_to_ord(&self, key: &T) -> Option<cmp::Ordering> { self.root.as_ref() .map(|p| &p.key) .map(|k| key.cmp(k)) } pub fn contains(& self, key: &T) -> bool { match self.map_to_ord(key) { Some(Less) => self.r_box().left.contains(key), Some(Greater) => self.r_box().right.contains(key), Some(Equal) => true, None => false, } } fn remove_self(&mut self, key: &T) { let mut c = self.node_take(); self.root = match (c.left.root.take(), c.right.root.take()) { (None, right) => right, (left, None) => left, (l@ Some(_), r@ Some(_)) => { let mut right = AvlTree{root: r}; mem::swap( &mut right.min().key, &mut c.key); c.right = right; c.left.root = l; c.right.remove(key); Some(c) } }; } pub fn iter<'a>(&'a self) -> TreeIterator<'a, T> { TreeIterator { current : self.root.as_ref(), path: Vec::new(), } } } pub struct TreeIterator<'a, T: 'a> where T: Ord { current : Option<&'a Box<Node<T>>>, path: Vec<&'a Box<Node<T>>>, } impl<'a, T> IntoIterator for & 'a AvlTree<T> where T: Ord { type Item = &'a T; type IntoIter = TreeIterator<'a, T>; fn into_iter(self) -> Self::IntoIter { self.iter() } } impl<'a, T> Iterator for TreeIterator<'a, T> where T: Ord { type Item = &'a T; fn next<'b>(&'b mut self) -> Option<Self::Item> { let mut c = self.current; while let Some(n) = c { self.path.push(n); c = n.left.root.as_ref(); } self.path.pop().map(|n|{ self.current = n.right.root.as_ref(); &n.key }) } } } |
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