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fix build_tree, binary_search_tree.cs

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fix two figures
This commit is contained in:
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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15
codes/typescript/chapter_divide_and_conquer/build_tree.ts
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@@ -10,8 +10,7 @@ import { TreeNode } from '../modules/TreeNode';
/* 构建二叉树：分治 */
function dfs(
preorder: number[],
inorder: number[],
hmap: Map<number, number>,
inorderMap: Map<number, number>,
i: number,
l: number,
r: number
@@ -21,11 +20,11 @@ function dfs(
// 初始化根节点
const root: TreeNode = 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;
}
@@ -33,11 +32,11 @@ function dfs(
/* 构建二叉树 */
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
let hmap = new Map<number, number>();
let inorderMap = new Map<number, number>();
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;
}