Mercurial > hg > Members > shoshi > AADS
view src/tree/AVLTreeMap.java @ 0:a9cb12a7f995
hg init
author | misaka |
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date | Wed, 06 Jul 2011 15:19:52 +0900 |
parents | |
children | 15920e9b562d |
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package tree; import java.util.LinkedList; import java.util.Random; public class AVLTreeMap<K extends Comparable<K>,V> implements Map<K,V> { private Node<K,V> root; private final Node<K,V> NULL_NODE = new Node<K,V>(null,null,-1,-1,null,null); public static void main(String args[]) { AVLTreeMap<Integer,String> map = new AVLTreeMap<Integer,String>(); Random r = new Random(); LinkedList<Integer> keys = new LinkedList<Integer>(); for(int i = 0;i < 30000;i ++){ int num = r.nextInt(); keys.add(num); map.put(num,Integer.toString(num)); } for(Integer key : keys){ String value = map.get(key); if(!key.toString().equals(value)){ System.out.println("gehoge"); } } System.out.println("hoge"); } public AVLTreeMap() { root = null; } @Override public void put(K key,V value) { if(root == null){ root = new Node<K,V>(key,value,0,0,NULL_NODE,NULL_NODE); return; } root = _put(root,key,value); } public Node<K,V> _put(Node<K,V> cur,K key,V value) { int result = cur.key.compareTo(key); if(result < 0){ //right if(cur.right == NULL_NODE){ cur.right = new Node<K,V>(key,value,0,0,NULL_NODE,NULL_NODE); cur.rdepth = 1; return cur; } cur.right = _put(cur.right,key,value); cur.rdepth = Math.max(cur.right.rdepth,cur.right.ldepth); int diff = cur.rdepth - cur.ldepth; if(diff > 1){ //一重回転か二重回転か判断する。 //以下の式は一重回転の場合は rottype が正になるはず。負の場合は二重回転、0の場合はあり得ない。 int rottype = result * cur.right.key.compareTo(key); if(rottype > 0){ return singleRotate(cur,OP_RIGHT); }else{ return doubleRotate(cur,OP_RIGHTLEFT); } } }else if(result > 0){ //left if(cur.left == NULL_NODE){ cur.left = new Node<K,V>(key,value,0,0,NULL_NODE,NULL_NODE); cur.ldepth = 1; return cur; } cur.left = _put(cur.left,key,value); cur.ldepth = Math.max(cur.left.ldepth,cur.left.rdepth) + 1; int diff = cur.ldepth - cur.rdepth; if(diff > 1){ //一重回転か二重回転か判断する。 //以下の式は一重回転の場合は rottype が正になるはず。負の場合は二重回転、0の場合はあり得ない。 int rottype = result * cur.left.key.compareTo(key); if(rottype > 0){ return singleRotate(cur,OP_LEFT); }else{ return doubleRotate(cur,OP_LEFTRIGHT); } } }else{ //find cur.value = value; } return cur; } private static final int OP_LEFT = 1; private static final int OP_RIGHT = 2; public Node<K,V> singleRotate(Node<K,V> target,int type) { switch(type){ case OP_LEFT: Node<K,V> left = target.left; target.left = left.right; left.right = target; target.ldepth = Math.max(target.left.rdepth,target.left.ldepth) + 1; left.rdepth = Math.max(left.right.rdepth,left.right.ldepth) + 1; return left; case OP_RIGHT: Node<K,V> right = target.right; target.right = right.left; right.left = target; target.rdepth = Math.max(target.right.rdepth,target.right.ldepth) + 1; right.ldepth = Math.max(right.left.ldepth,right.left.rdepth) + 1; return right; default: throw new IllegalArgumentException("invalid rotation type"); } } private static final int OP_LEFTRIGHT = 1; private static final int OP_RIGHTLEFT = 2; public Node<K,V> doubleRotate(Node<K,V> target,int type) { switch(type){ case OP_LEFTRIGHT: target.left = singleRotate(target.left,OP_RIGHT); return singleRotate(target,OP_LEFT); case OP_RIGHTLEFT: target.right = singleRotate(target.right,OP_LEFT); return singleRotate(target,OP_RIGHT); default: throw new IllegalArgumentException("invalid rotation type."); } } @Override public V get(K key) { Node<K,V> cur = root; while(cur != NULL_NODE){ int result = cur.key.compareTo(key); if(result < 0){ cur = cur.right; }else if(result > 0){ cur = cur.left; }else{ //find break; } } return cur.value; } @Override public V remove(K key) { } private Node<K,V> _remove(K key) { } private static class Node<K,V> { K key; V value; Node<K,V> left; Node<K,V> right; int ldepth; int rdepth; public Node(K key,V value,int rdepth,int ldepth,Node<K,V> left,Node<K,V> right) { this.key = key; this.value = value; this.ldepth = ldepth; this.rdepth = rdepth; this.left = left; this.right = right; } @Override public String toString() { return "[" + key + ":" + value + "]"; } } }