fix build_tree, binary_search_tree.cs
fix two figures
This commit is contained in:
parent
af2aeb0897
commit
cb9c14f5ff
@ -7,18 +7,18 @@
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#include "../utils/common.hpp"
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#include "../utils/common.hpp"
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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TreeNode *dfs(vector<int> &preorder, vector<int> &inorder, unordered_map<int, int> &hmap, int i, int l, int r) {
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TreeNode *dfs(vector<int> &preorder, unordered_map<int, int> &inorderMap, int i, int l, int r) {
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// 子树区间为空时终止
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// 子树区间为空时终止
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if (r - l < 0)
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if (r - l < 0)
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return NULL;
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return NULL;
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// 初始化根节点
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// 初始化根节点
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TreeNode *root = new TreeNode(preorder[i]);
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TreeNode *root = new TreeNode(preorder[i]);
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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int m = hmap[preorder[i]];
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int m = inorderMap[preorder[i]];
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// 子问题:构建左子树
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// 子问题:构建左子树
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root->left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
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root->left = dfs(preorder, inorderMap, i + 1, l, m - 1);
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// 子问题:构建右子树
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// 子问题:构建右子树
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root->right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
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root->right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
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// 返回根节点
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// 返回根节点
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return root;
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return root;
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}
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}
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@ -26,11 +26,11 @@ TreeNode *dfs(vector<int> &preorder, vector<int> &inorder, unordered_map<int, in
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/* 构建二叉树 */
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/* 构建二叉树 */
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TreeNode *buildTree(vector<int> &preorder, vector<int> &inorder) {
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TreeNode *buildTree(vector<int> &preorder, vector<int> &inorder) {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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unordered_map<int, int> hmap;
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unordered_map<int, int> inorderMap;
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for (int i = 0; i < inorder.size(); i++) {
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for (int i = 0; i < inorder.size(); i++) {
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hmap[inorder[i]] = i;
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inorderMap[inorder[i]] = i;
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}
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}
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TreeNode *root = dfs(preorder, inorder, hmap, 0, 0, inorder.size() - 1);
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TreeNode *root = dfs(preorder, inorderMap, 0, 0, inorder.size() - 1);
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return root;
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return root;
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}
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}
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@ -8,18 +8,18 @@ namespace hello_algo.chapter_divide_and_conquer;
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public class build_tree {
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public class build_tree {
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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public TreeNode dfs(int[] preorder, int[] inorder, Dictionary<int, int> hmap, int i, int l, int r) {
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public TreeNode dfs(int[] preorder, Dictionary<int, int> inorderMap, int i, int l, int r) {
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// 子树区间为空时终止
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// 子树区间为空时终止
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if (r - l < 0)
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if (r - l < 0)
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return null;
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return null;
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// 初始化根节点
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// 初始化根节点
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TreeNode root = new TreeNode(preorder[i]);
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TreeNode root = new TreeNode(preorder[i]);
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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int m = hmap[preorder[i]];
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int m = inorderMap[preorder[i]];
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// 子问题:构建左子树
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// 子问题:构建左子树
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root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
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root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
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// 子问题:构建右子树
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// 子问题:构建右子树
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root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
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root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
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// 返回根节点
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// 返回根节点
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return root;
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return root;
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}
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}
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@ -27,11 +27,11 @@ public class build_tree {
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/* 构建二叉树 */
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/* 构建二叉树 */
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public TreeNode buildTree(int[] preorder, int[] inorder) {
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public TreeNode buildTree(int[] preorder, int[] inorder) {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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Dictionary<int, int> hmap = new Dictionary<int, int>();
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Dictionary<int, int> inorderMap = new Dictionary<int, int>();
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for (int i = 0; i < inorder.Length; i++) {
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for (int i = 0; i < inorder.Length; i++) {
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hmap.TryAdd(inorder[i], i);
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inorderMap.TryAdd(inorder[i], i);
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}
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}
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TreeNode root = dfs(preorder, inorder, hmap, 0, 0, inorder.Length - 1);
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TreeNode root = dfs(preorder, inorderMap, 0, 0, inorder.Length - 1);
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return root;
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return root;
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}
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}
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@ -91,7 +91,7 @@ class BinarySearchTree {
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cur = cur.left;
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cur = cur.left;
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}
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}
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// 若无待删除节点,则直接返回
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// 若无待删除节点,则直接返回
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if (cur == null || pre == null)
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if (cur == null)
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return;
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return;
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// 子节点数量 = 0 or 1
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// 子节点数量 = 0 or 1
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if (cur.left == null || cur.right == null) {
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if (cur.left == null || cur.right == null) {
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@ -10,8 +10,7 @@ import '../utils/tree_node.dart';
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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TreeNode? dfs(
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TreeNode? dfs(
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List<int> preorder,
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List<int> preorder,
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List<int> inorder,
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Map<int, int> inorderMap,
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Map<int, int> hmap,
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int i,
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int i,
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int l,
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int l,
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int r,
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int r,
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@ -23,11 +22,11 @@ TreeNode? dfs(
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// 初始化根节点
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// 初始化根节点
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TreeNode? root = TreeNode(preorder[i]);
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TreeNode? root = TreeNode(preorder[i]);
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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int m = hmap[preorder[i]]!;
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int m = inorderMap[preorder[i]]!;
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// 子问题:构建左子树
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// 子问题:构建左子树
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root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
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root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
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// 子问题:构建右子树
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// 子问题:构建右子树
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root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
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root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
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// 返回根节点
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// 返回根节点
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return root;
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return root;
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}
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}
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@ -35,11 +34,11 @@ TreeNode? dfs(
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/* 构建二叉树 */
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/* 构建二叉树 */
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TreeNode? buildTree(List<int> preorder, List<int> inorder) {
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TreeNode? buildTree(List<int> preorder, List<int> inorder) {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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Map<int, int> hmap = {};
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Map<int, int> inorderMap = {};
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for (int i = 0; i < inorder.length; i++) {
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for (int i = 0; i < inorder.length; i++) {
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hmap[inorder[i]] = i;
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inorderMap[inorder[i]] = i;
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}
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}
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TreeNode? root = dfs(preorder, inorder, hmap, 0, 0, inorder.length - 1);
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TreeNode? root = dfs(preorder, inorderMap, 0, 0, inorder.length - 1);
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return root;
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return root;
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}
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}
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@ -7,7 +7,7 @@ package chapter_divide_and_conquer
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import . "github.com/krahets/hello-algo/pkg"
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import . "github.com/krahets/hello-algo/pkg"
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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func dfsBuildTree(preorder, inorder []int, hmap map[int]int, i, l, r int) *TreeNode {
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func dfsBuildTree(preorder []int, inorderMap map[int]int, i, l, r int) *TreeNode {
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// 子树区间为空时终止
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// 子树区间为空时终止
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if r-l < 0 {
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if r-l < 0 {
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return nil
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return nil
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@ -15,11 +15,11 @@ func dfsBuildTree(preorder, inorder []int, hmap map[int]int, i, l, r int) *TreeN
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// 初始化根节点
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// 初始化根节点
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root := NewTreeNode(preorder[i])
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root := NewTreeNode(preorder[i])
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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m := hmap[preorder[i]]
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m := inorderMap[preorder[i]]
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// 子问题:构建左子树
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// 子问题:构建左子树
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root.Left = dfsBuildTree(preorder, inorder, hmap, i+1, l, m-1)
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root.Left = dfsBuildTree(preorder, inorderMap, i+1, l, m-1)
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// 子问题:构建右子树
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// 子问题:构建右子树
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root.Right = dfsBuildTree(preorder, inorder, hmap, i+1+m-l, m+1, r)
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root.Right = dfsBuildTree(preorder, inorderMap, i+1+m-l, m+1, r)
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// 返回根节点
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// 返回根节点
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return root
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return root
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}
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}
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@ -27,11 +27,11 @@ func dfsBuildTree(preorder, inorder []int, hmap map[int]int, i, l, r int) *TreeN
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/* 构建二叉树 */
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/* 构建二叉树 */
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func buildTree(preorder, inorder []int) *TreeNode {
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func buildTree(preorder, inorder []int) *TreeNode {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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hmap := make(map[int]int, len(inorder))
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inorderMap := make(map[int]int, len(inorder))
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for i := 0; i < len(inorder); i++ {
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for i := 0; i < len(inorder); i++ {
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hmap[inorder[i]] = i
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inorderMap[inorder[i]] = i
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}
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}
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root := dfsBuildTree(preorder, inorder, hmap, 0, 0, len(inorder)-1)
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root := dfsBuildTree(preorder, inorderMap, 0, 0, len(inorder)-1)
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return root
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return root
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}
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}
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@ -11,18 +11,18 @@ import java.util.*;
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public class build_tree {
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public class build_tree {
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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static TreeNode dfs(int[] preorder, int[] inorder, Map<Integer, Integer> hmap, int i, int l, int r) {
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static TreeNode dfs(int[] preorder, Map<Integer, Integer> inorderMap, int i, int l, int r) {
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// 子树区间为空时终止
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// 子树区间为空时终止
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if (r - l < 0)
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if (r - l < 0)
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return null;
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return null;
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// 初始化根节点
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// 初始化根节点
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TreeNode root = new TreeNode(preorder[i]);
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TreeNode root = new TreeNode(preorder[i]);
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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int m = hmap.get(preorder[i]);
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int m = inorderMap.get(preorder[i]);
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// 子问题:构建左子树
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// 子问题:构建左子树
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root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
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root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
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// 子问题:构建右子树
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// 子问题:构建右子树
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root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
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root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
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// 返回根节点
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// 返回根节点
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return root;
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return root;
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}
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}
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@ -30,11 +30,11 @@ public class build_tree {
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/* 构建二叉树 */
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/* 构建二叉树 */
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static TreeNode buildTree(int[] preorder, int[] inorder) {
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static TreeNode buildTree(int[] preorder, int[] inorder) {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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Map<Integer, Integer> hmap = new HashMap<>();
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Map<Integer, Integer> inorderMap = new HashMap<>();
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for (int i = 0; i < inorder.length; i++) {
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for (int i = 0; i < inorder.length; i++) {
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hmap.put(inorder[i], i);
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inorderMap.put(inorder[i], i);
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}
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}
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TreeNode root = dfs(preorder, inorder, hmap, 0, 0, inorder.length - 1);
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TreeNode root = dfs(preorder, inorderMap, 0, 0, inorder.length - 1);
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return root;
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return root;
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}
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}
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@ -8,17 +8,17 @@ const { printTree } = require('../modules/PrintUtil');
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const { TreeNode } = require('../modules/TreeNode');
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const { TreeNode } = require('../modules/TreeNode');
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/* 构建二叉树:分治 */
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/* 构建二叉树:分治 */
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function dfs(preorder, inorder, hmap, i, l, r) {
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function dfs(preorder, inorderMap, i, l, r) {
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// 子树区间为空时终止
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// 子树区间为空时终止
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if (r - l < 0) return null;
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if (r - l < 0) return null;
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// 初始化根节点
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// 初始化根节点
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const root = new TreeNode(preorder[i]);
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const root = new TreeNode(preorder[i]);
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// 查询 m ,从而划分左右子树
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// 查询 m ,从而划分左右子树
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const m = hmap.get(preorder[i]);
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const m = inorderMap.get(preorder[i]);
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// 子问题:构建左子树
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// 子问题:构建左子树
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root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
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root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
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// 子问题:构建右子树
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// 子问题:构建右子树
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root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
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root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
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// 返回根节点
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// 返回根节点
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return root;
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return root;
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}
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}
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@ -26,11 +26,11 @@ function dfs(preorder, inorder, hmap, i, l, r) {
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/* 构建二叉树 */
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/* 构建二叉树 */
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function buildTree(preorder, inorder) {
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function buildTree(preorder, inorder) {
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// 初始化哈希表,存储 inorder 元素到索引的映射
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// 初始化哈希表,存储 inorder 元素到索引的映射
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let hmap = new Map();
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let inorderMap = new Map();
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for (let i = 0; i < inorder.length; i++) {
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for (let i = 0; i < inorder.length; i++) {
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hmap.set(inorder[i], i);
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inorderMap.set(inorder[i], i);
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}
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}
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const root = dfs(preorder, inorder, hmap, 0, 0, inorder.length - 1);
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const root = dfs(preorder, inorderMap, 0, 0, inorder.length - 1);
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return root;
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return root;
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}
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}
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@ -12,8 +12,7 @@ from modules import *
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def dfs(
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def dfs(
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preorder: list[int],
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preorder: list[int],
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inorder: list[int],
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inorder_map: dict[int, int],
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hmap: dict[int, int],
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i: int,
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i: int,
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l: int,
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l: int,
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r: int,
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r: int,
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@ -25,11 +24,11 @@ def dfs(
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# 初始化根节点
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# 初始化根节点
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root = TreeNode(preorder[i])
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root = TreeNode(preorder[i])
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# 查询 m ,从而划分左右子树
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# 查询 m ,从而划分左右子树
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m = hmap[preorder[i]]
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m = inorder_map[preorder[i]]
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# 子问题:构建左子树
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# 子问题:构建左子树
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root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1)
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root.left = dfs(preorder, inorder_map, i + 1, l, m - 1)
|
||||||
# 子问题:构建右子树
|
# 子问题:构建右子树
|
||||||
root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r)
|
root.right = dfs(preorder, inorder_map, i + 1 + m - l, m + 1, r)
|
||||||
# 返回根节点
|
# 返回根节点
|
||||||
return root
|
return root
|
||||||
|
|
||||||
@ -37,8 +36,8 @@ def dfs(
|
|||||||
def build_tree(preorder: list[int], inorder: list[int]) -> TreeNode | None:
|
def build_tree(preorder: list[int], inorder: list[int]) -> TreeNode | None:
|
||||||
"""构建二叉树"""
|
"""构建二叉树"""
|
||||||
# 初始化哈希表,存储 inorder 元素到索引的映射
|
# 初始化哈希表,存储 inorder 元素到索引的映射
|
||||||
hmap = {val: i for i, val in enumerate(inorder)}
|
inorder_map = {val: i for i, val in enumerate(inorder)}
|
||||||
root = dfs(preorder, inorder, hmap, 0, 0, len(inorder) - 1)
|
root = dfs(preorder, inorder_map, 0, 0, len(inorder) - 1)
|
||||||
return root
|
return root
|
||||||
|
|
||||||
|
|
||||||
|
@ -10,17 +10,17 @@ include!("../include/include.rs");
|
|||||||
use tree_node::TreeNode;
|
use tree_node::TreeNode;
|
||||||
|
|
||||||
/* 构建二叉树:分治 */
|
/* 构建二叉树:分治 */
|
||||||
fn dfs(preorder: &[i32], inorder: &[i32], hmap: &HashMap<i32, i32>, i: i32, l: i32, r: i32) -> Option<Rc<RefCell<TreeNode>>> {
|
fn dfs(preorder: &[i32], inorderMap: &HashMap<i32, i32>, i: i32, l: i32, r: i32) -> Option<Rc<RefCell<TreeNode>>> {
|
||||||
// 子树区间为空时终止
|
// 子树区间为空时终止
|
||||||
if r - l < 0 { return None; }
|
if r - l < 0 { return None; }
|
||||||
// 初始化根节点
|
// 初始化根节点
|
||||||
let root = TreeNode::new(preorder[i as usize]);
|
let root = TreeNode::new(preorder[i as usize]);
|
||||||
// 查询 m ,从而划分左右子树
|
// 查询 m ,从而划分左右子树
|
||||||
let m = hmap.get(&preorder[i as usize]).unwrap();
|
let m = inorderMap.get(&preorder[i as usize]).unwrap();
|
||||||
// 子问题:构建左子树
|
// 子问题:构建左子树
|
||||||
root.borrow_mut().left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
|
root.borrow_mut().left = dfs(preorder, inorderMap, i + 1, l, m - 1);
|
||||||
// 子问题:构建右子树
|
// 子问题:构建右子树
|
||||||
root.borrow_mut().right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
|
root.borrow_mut().right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
|
||||||
// 返回根节点
|
// 返回根节点
|
||||||
Some(root)
|
Some(root)
|
||||||
}
|
}
|
||||||
@ -28,11 +28,11 @@ fn dfs(preorder: &[i32], inorder: &[i32], hmap: &HashMap<i32, i32>, i: i32, l: i
|
|||||||
/* 构建二叉树 */
|
/* 构建二叉树 */
|
||||||
fn build_tree(preorder: &[i32], inorder: &[i32]) -> Option<Rc<RefCell<TreeNode>>> {
|
fn build_tree(preorder: &[i32], inorder: &[i32]) -> Option<Rc<RefCell<TreeNode>>> {
|
||||||
// 初始化哈希表,存储 inorder 元素到索引的映射
|
// 初始化哈希表,存储 inorder 元素到索引的映射
|
||||||
let mut hmap: HashMap<i32, i32> = HashMap::new();
|
let mut inorderMap: HashMap<i32, i32> = HashMap::new();
|
||||||
for i in 0..inorder.len() {
|
for i in 0..inorder.len() {
|
||||||
hmap.insert(inorder[i], i as i32);
|
inorderMap.insert(inorder[i], i as i32);
|
||||||
}
|
}
|
||||||
let root = dfs(preorder, inorder, &hmap, 0, 0, inorder.len() as i32 - 1);
|
let root = dfs(preorder, &inorderMap, 0, 0, inorder.len() as i32 - 1);
|
||||||
root
|
root
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -7,7 +7,7 @@
|
|||||||
import utils
|
import utils
|
||||||
|
|
||||||
/* 构建二叉树:分治 */
|
/* 构建二叉树:分治 */
|
||||||
func dfs(preorder: [Int], inorder: [Int], hmap: [Int: Int], i: Int, l: Int, r: Int) -> TreeNode? {
|
func dfs(preorder: [Int], inorderMap: [Int: Int], i: Int, l: Int, r: Int) -> TreeNode? {
|
||||||
// 子树区间为空时终止
|
// 子树区间为空时终止
|
||||||
if r - l < 0 {
|
if r - l < 0 {
|
||||||
return nil
|
return nil
|
||||||
@ -15,11 +15,11 @@ func dfs(preorder: [Int], inorder: [Int], hmap: [Int: Int], i: Int, l: Int, r: I
|
|||||||
// 初始化根节点
|
// 初始化根节点
|
||||||
let root = TreeNode(x: preorder[i])
|
let root = TreeNode(x: preorder[i])
|
||||||
// 查询 m ,从而划分左右子树
|
// 查询 m ,从而划分左右子树
|
||||||
let m = hmap[preorder[i]]!
|
let m = inorderMap[preorder[i]]!
|
||||||
// 子问题:构建左子树
|
// 子问题:构建左子树
|
||||||
root.left = dfs(preorder: preorder, inorder: inorder, hmap: hmap, i: i + 1, l: l, r: m - 1)
|
root.left = dfs(preorder: preorder, inorderMap: inorderMap, i: i + 1, l: l, r: m - 1)
|
||||||
// 子问题:构建右子树
|
// 子问题:构建右子树
|
||||||
root.right = dfs(preorder: preorder, inorder: inorder, hmap: hmap, i: i + 1 + m - l, l: m + 1, r: r)
|
root.right = dfs(preorder: preorder, inorderMap: inorderMap, i: i + 1 + m - l, l: m + 1, r: r)
|
||||||
// 返回根节点
|
// 返回根节点
|
||||||
return root
|
return root
|
||||||
}
|
}
|
||||||
@ -27,8 +27,8 @@ func dfs(preorder: [Int], inorder: [Int], hmap: [Int: Int], i: Int, l: Int, r: I
|
|||||||
/* 构建二叉树 */
|
/* 构建二叉树 */
|
||||||
func buildTree(preorder: [Int], inorder: [Int]) -> TreeNode? {
|
func buildTree(preorder: [Int], inorder: [Int]) -> TreeNode? {
|
||||||
// 初始化哈希表,存储 inorder 元素到索引的映射
|
// 初始化哈希表,存储 inorder 元素到索引的映射
|
||||||
let hmap = inorder.enumerated().reduce(into: [:]) { $0[$1.element] = $1.offset }
|
let inorderMap = inorder.enumerated().reduce(into: [:]) { $0[$1.element] = $1.offset }
|
||||||
return dfs(preorder: preorder, inorder: inorder, hmap: hmap, i: 0, l: 0, r: inorder.count - 1)
|
return dfs(preorder: preorder, inorderMap: inorderMap, i: 0, l: 0, r: inorder.count - 1)
|
||||||
}
|
}
|
||||||
|
|
||||||
@main
|
@main
|
||||||
|
@ -10,8 +10,7 @@ import { TreeNode } from '../modules/TreeNode';
|
|||||||
/* 构建二叉树:分治 */
|
/* 构建二叉树:分治 */
|
||||||
function dfs(
|
function dfs(
|
||||||
preorder: number[],
|
preorder: number[],
|
||||||
inorder: number[],
|
inorderMap: Map<number, number>,
|
||||||
hmap: Map<number, number>,
|
|
||||||
i: number,
|
i: number,
|
||||||
l: number,
|
l: number,
|
||||||
r: number
|
r: number
|
||||||
@ -21,11 +20,11 @@ function dfs(
|
|||||||
// 初始化根节点
|
// 初始化根节点
|
||||||
const root: TreeNode = new TreeNode(preorder[i]);
|
const root: TreeNode = new TreeNode(preorder[i]);
|
||||||
// 查询 m ,从而划分左右子树
|
// 查询 m ,从而划分左右子树
|
||||||
const m = hmap.get(preorder[i]);
|
const m = inorderMap.get(preorder[i]);
|
||||||
// 子问题:构建左子树
|
// 子问题:构建左子树
|
||||||
root.left = dfs(preorder, inorder, hmap, i + 1, l, m - 1);
|
root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
|
||||||
// 子问题:构建右子树
|
// 子问题:构建右子树
|
||||||
root.right = dfs(preorder, inorder, hmap, i + 1 + m - l, m + 1, r);
|
root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
|
||||||
// 返回根节点
|
// 返回根节点
|
||||||
return root;
|
return root;
|
||||||
}
|
}
|
||||||
@ -33,11 +32,11 @@ function dfs(
|
|||||||
/* 构建二叉树 */
|
/* 构建二叉树 */
|
||||||
function buildTree(preorder: number[], inorder: number[]): TreeNode | null {
|
function buildTree(preorder: number[], inorder: number[]): TreeNode | null {
|
||||||
// 初始化哈希表,存储 inorder 元素到索引的映射
|
// 初始化哈希表,存储 inorder 元素到索引的映射
|
||||||
let hmap = new Map<number, number>();
|
let inorderMap = new Map<number, number>();
|
||||||
for (let i = 0; i < inorder.length; i++) {
|
for (let i = 0; i < inorder.length; i++) {
|
||||||
hmap.set(inorder[i], i);
|
inorderMap.set(inorder[i], i);
|
||||||
}
|
}
|
||||||
const root = dfs(preorder, inorder, hmap, 0, 0, inorder.length - 1);
|
const root = dfs(preorder, inorderMap, 0, 0, inorder.length - 1);
|
||||||
return root;
|
return root;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
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Loading…
Reference in New Issue
Block a user