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fix build_tree, binary_search_tree.cs

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fix two figures
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krahets
2023-09-15 02:08:09 +08:00
parent af2aeb0897
commit cb9c14f5ff
13 changed files with 69 additions and 72 deletions
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14
codes/javascript/chapter_divide_and_conquer/build_tree.js
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@@ -8,17 +8,17 @@ const { printTree } = require('../modules/PrintUtil');
const { TreeNode } = require('../modules/TreeNode');
/* 构建二叉树：分治 */
function dfs(preorder, inorder, hmap, i, l, r) {
function dfs(preorder, inorderMap, i, l, r) {
// 子树区间为空时终止
if (r - l < 0) return null;
// 初始化根节点
const root = new TreeNode(preorder[i]);
// 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
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
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
return root;
}
@@ -26,11 +26,11 @@ function dfs(preorder, inorder, hmap, i, l, r) {
/* 构建二叉树 */
function buildTree(preorder, inorder) {
// 初始化哈希表，存储 inorder 元素到索引的映射
let hmap = new Map();
let inorderMap = new Map();
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;
}