feat(chapter_backtracking): Add js and ts codes for chapter 13.3 (#667)

* feat(chapter_dynamic_programming): Add js and ts codes for chapter 14.1

* style(chapter_dynamic_programming): format code

* refactor(chapter_dynamic_programming): remove main definition and add type

* feat(chapter_backtracking): Add js and ts codes for chapter 13.3

* feat(chapter_divide_and_conquer): Add js and ts codes for chapter 12.2

* feat(chapter_divide_and_conquer): Add js and ts codes for chapter 12.3

* feat(chapter_divide_and_conquer): Add js and ts codes for chapter 12.4

* style(chapter_divide_and_conquer): fix typo

* refactor: Use === instead of == in js and ts

codes/javascript/chapter_divide_and_conquer/binary_search_recur.js

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+/**
+ * File: binary_search_recur.js
+ * Created Time: 2023-07-30
+ * Author: yuan0221 (yl1452491917@gmail.com)
+ */
+
+/* 二分查找：问题 f(i, j) */
+function dfs(nums, target, i, j) {
+    // 若区间为空，代表无目标元素，则返回 -1
+    if (i > j) {
+        return -1;
+    }
+    // 计算中点索引 m
+    const m = i + ((j - i) >> 1);
+    if (nums[m] < target) {
+        // 递归子问题 f(m+1, j)
+        return dfs(nums, target, m + 1, j);
+    } else if (nums[m] > target) {
+        // 递归子问题 f(i, m-1)
+        return dfs(nums, target, i, m - 1);
+    } else {
+        // 找到目标元素，返回其索引
+        return m;
+    }
+}
+
+/* 二分查找 */
+function binarySearch(nums, target) {
+    const n = nums.length;
+    // 求解问题 f(0, n-1)
+    return dfs(nums, target, 0, n - 1);
+}
+
+/* Driver Code */
+const target = 6;
+const nums = [1, 3, 6, 8, 12, 15, 23, 26, 31, 35];
+// 二分查找（双闭区间）
+const index = binarySearch(nums, target);
+console.log(`目标元素 6 的索引 = ${index}`);

codes/javascript/chapter_divide_and_conquer/build_tree.js

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+/**
+ * File: build_tree.js
+ * Created Time: 2023-07-30
+ * Author: yuan0221 (yl1452491917@gmail.com)
+ */
+
+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) {
+    // 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]);
+    // 子问题：构建左子树
+    root.left = dfs(preorder, inorder, hmap, 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);
+    // 返回根节点
+    return root;
+}
+
+/* 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();
+    for (let i = 0; i < inorder.length; i++) {
+        hmap.set(inorder[i], i);
+    }
+    const root = dfs(preorder, inorder, hmap, 0, 0, inorder.length - 1);
+    return root;
+}
+
+/* Driver Code */
+const preorder = [3, 9, 2, 1, 7];
+const inorder = [9, 3, 1, 2, 7];
+console.log('前序遍历 = ' + JSON.stringify(preorder));
+console.log('中序遍历 = ' + JSON.stringify(inorder));
+const root = buildTree(preorder, inorder);
+console.log('构建的二叉树为：');
+printTree(root);

codes/javascript/chapter_divide_and_conquer/hanota.js

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+/**
+ * File: hanota.js
+ * Created Time: 2023-07-30
+ * Author: yuan0221 (yl1452491917@gmail.com)
+ */
+
+/* 移动一个圆盘 */
+function move(src, tar) {
+    // 从 src 顶部拿出一个圆盘
+    const pan = src.pop();
+    // 将圆盘放入 tar 顶部
+    tar.push(pan);
+}
+
+/* 求解汉诺塔：问题 f(i) */
+function dfs(i, src, buf, tar) {
+    // 若 src 只剩下一个圆盘，则直接将其移到 tar
+    if (i === 1) {
+        move(src, tar);
+        return;
+    }
+    // 子问题 f(i-1) ：将 src 顶部 i-1 个圆盘借助 tar 移到 buf
+    dfs(i - 1, src, tar, buf);
+    // 子问题 f(1) ：将 src 剩余一个圆盘移到 tar
+    move(src, tar);
+    // 子问题 f(i-1) ：将 buf 顶部 i-1 个圆盘借助 src 移到 tar
+    dfs(i - 1, buf, src, tar);
+}
+
+/* 求解汉诺塔 */
+function solveHanota(A, B, C) {
+    const n = A.length;
+    // 将 A 顶部 n 个圆盘借助 B 移到 C
+    dfs(n, A, B, C);
+}
+
+/* Driver Code */
+// 列表尾部是柱子顶部
+const A = [5, 4, 3, 2, 1];
+const B = [];
+const C = [];
+console.log('初始状态下：');
+console.log(`A = ${JSON.stringify(A)}`);
+console.log(`B = ${JSON.stringify(B)}`);
+console.log(`C = ${JSON.stringify(C)}`);
+
+solveHanota(A, B, C);
+
+console.log('圆盘移动完成后：');
+console.log(`A = ${JSON.stringify(A)}`);
+console.log(`B = ${JSON.stringify(B)}`);
+console.log(`C = ${JSON.stringify(C)}`);