https://leetcode.cn/problems/maximum-binary-tree-ii/ https://leetcode.cn/problems/maximum-binary-tree/

Author: masx200

README.md

@@ -10,6 +10,10 @@ leetcode 测试
 
 ##### 包含的内容如下
 
+https://leetcode.cn/problems/maximum-binary-tree-ii/
+
+https://leetcode.cn/problems/maximum-binary-tree/
+
 https://leetcode-cn.com/problems/number-of-students-doing-homework-at-a-given-time/
 
 https://leetcode.cn/problems/number-of-digit-one/

maximum-binary-tree-ii/index.ts

@@ -0,0 +1,17 @@
+import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
+
+export default function insertIntoMaxTree(
+    root: TreeNode | null,
+    val: number,
+): TreeNode | null {
+    // 如果root是空节点的话，就以val返回一个新节点
+    // 如果 val 是整棵树最大的，那么原来的这棵树应该是 val 节点的左子树，因为 val 节点是接在原始数组 a 的最后一个元素
+    if (root == null || root.val < val) {
+        return new TreeNode(val, root);
+    } // 如果 val 不是最大的，那么就应该在右子树上，因为 val 节点是接在原始数组 a 的最后一个元素
+    else {
+        root.right = insertIntoMaxTree(root.right, val);
+
+        return root;
+    }
+}

maximum-binary-tree-ii/test.ts

@@ -0,0 +1,24 @@
+import { assertEquals } from "../deps.ts";
+import { TreeNodeLeetCodeParse } from "../mod.ts";
+import constructMaximumBinaryTreeII from "./index.ts";
+Deno.test("maximum-binary-tree-ii", () => {
+    const inputs: Array<[(number | null)[], number]> = [
+        [[4, 1, 3, null, null, 2], 5],
+        [[5, 2, 4, null, 1], 3],
+        [[5, 2, 3, null, 1], 4],
+    ];
+    const outputs = [
+        [5, 4, null, 1, 3, null, null, 2],
+        [5, 2, 4, null, 1, null, 3],
+        [5, 2, 4, null, 1, 3],
+    ];
+    assertEquals(
+        inputs.map(([input, k]) =>
+            constructMaximumBinaryTreeII(
+                TreeNodeLeetCodeParse(JSON.stringify(input)),
+                k,
+            )
+        ),
+        outputs.map((a) => TreeNodeLeetCodeParse(JSON.stringify(a))),
+    );
+});

maximum-binary-tree/index.ts

@@ -0,0 +1,11 @@
+import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
+import insertIntoMaxTree from "../maximum-binary-tree-ii/index.ts";
+
+export default function constructMaximumBinaryTree(
+    nums: number[],
+): TreeNode | null {
+    return nums.reduce(
+        (a: TreeNode | null, v: number) => insertIntoMaxTree(a, v),
+        null,
+    );
+}

maximum-binary-tree/test.ts

@@ -0,0 +1,20 @@
+import { assertEquals } from "../deps.ts";
+import { TreeNodeLeetCodeStringify } from "../mod.ts";
+import constructMaximumBinaryTree from "./index.ts";
+
+Deno.test("maximum-binary-tree", () => {
+    const inputs = [
+        [3, 2, 1, 6, 0, 5],
+        [3, 2, 1],
+    ];
+    const outputs = [
+        [6, 3, 5, null, 2, 0, null, null, 1],
+        [3, null, 2, null, 1],
+    ];
+    assertEquals(
+        inputs
+            .map((input) => constructMaximumBinaryTree(input))
+            .map((a) => TreeNodeLeetCodeStringify(a)),
+        outputs.map((a) => JSON.stringify(a)),
+    );
+});

utils/TreeNodeLeetCodeParse.ts

@@ -1,5 +1,15 @@
 import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
 import { TreeNode as TreeNodeClass } from "../deps.ts";
 export function TreeNodeLeetCodeParse(s: string): TreeNode | null {
-    return TreeNodeClass.create(JSON.parse(s));
+    return treeNodeNew(TreeNodeClass.create(JSON.parse(s)));
+}
+function treeNodeNew(t: TreeNodeClass | null): TreeNode | null {
+    if (t == null) {
+        return null;
+    }
+    const n = new TreeNode();
+    n.val = t.val;
+    n.left = treeNodeNew(t.left);
+    n.right = treeNodeNew(t.right);
+    return n;
 }

utils/TreeNodeLeetCodeStringify.ts

@@ -1,5 +1,15 @@
 import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
 import { TreeNode as TreeNodeClass } from "../deps.ts";
 export function TreeNodeLeetCodeStringify(root: TreeNode | null): string {
-    return JSON.stringify(TreeNodeClass.show(root));
+    return JSON.stringify(TreeNodeClass.show(treeNodeCreate(root)));
+}
+function treeNodeCreate(t: TreeNode | null): TreeNodeClass | null {
+    if (t == null) {
+        return null;
+    }
+    const n = new TreeNodeClass();
+    n.val = t.val;
+    n.left = treeNodeCreate(t.left);
+    n.right = treeNodeCreate(t.right);
+    return n;
 }

utils/go.sum

@@ -1,6 +1,8 @@
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/egregors/TreeNode v1.0.3 h1:oSel21BpUt99TWGrFJ1QbSBBEeQSdwOqOpX9eSqILNE=
 github.com/egregors/TreeNode v1.0.3/go.mod h1:c2sTJKaqtn/Ju3J7rFi6RvJqbLFAEObRDJP6yqRCdaA=
+github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gotest.tools/v3 v3.3.0 h1:MfDY1b1/0xN1CyMlQDac0ziEy9zJQd9CXBRRDHw2jJo=