优化目录结构

Author: wangjieCode

main.js

@@ -8,6 +8,11 @@ const b = new ListNode(2)
 const c = new ListNode(4)
 a.next = b
 b.next = c
+
+c.next = a;
+
+console.log( isCircularLinkList(a) )
+
 const d = new ListNode(1)
 const e = new ListNode(3)
 const f = new ListNode(4)
@@ -24,70 +29,8 @@ function bianli(root, vals = []) {
 // bianli(a)
 // bianli(d)
 
-/** 迭代法
- * @param {ListNode} l1
- * @param {ListNode} l2
- * @return {ListNode}
- */
-var mergeTwoLists = function (l1, l2) {
-    let res = new ListNode();
-    let root = res
-    while (l1 !== null && l2 !== null) {
-        if (l1.val <= l2.val) {
-            root.next = l1;
-            l1 = l1.next;
-        } else {
-            root.next = l2
-            l2 = l2.next;
-        }
-        root = root.next
-    }
-    if (l1 != null) {
-        root.next = l1;
-    }
 
-    if (l2 != null) {
-        root.next = l2;
-    }
-    return res.next
-};
-
-/**转化数组法
- * @param {ListNode} l1
- * @param {ListNode} l2
- * @return {ListNode}
- */
-var mergeTwoLists2 = function (l1, l2) {
-    if (l1 == null && l2 == null) return l1
-    const l1res = bianli(l1)
-    const l2res = bianli(l2)
-    const resData = [...l1res, ...l2res].sort((a, b) => a - b)
-    let root = new ListNode(resData[0]);
-    let res = root;
-    for (let i = 1; i < resData.length; i++) {
-        res.next = new ListNode(resData[i])
-        res = res.next;
-    }
-    return root
-};
+// console.log(bianli(mergeTwoLists3(a, d)))
 
-
-/**递归
- * @param {ListNode} l1
- * @param {ListNode} l2
- * @return {ListNode}
- */
-var mergeTwoLists3 = function (l1, l2) {
-    if (l1 == null) {
-        return l2;
-    } else if (l2 == null) {
-        return l1;
-    } else if (l1.val < l2.val) {
-        l1.next = mergeTwoLists(l1.next, l2);
-        return l1;
-    } else {
-        l2.next = mergeTwoLists(l1, l2.next);
-        return l2;
-    }
-};
-console.log(bianli(mergeTwoLists3(a, d)))
+import './链表/myLinkList.js'
+import { isCircularLinkList } from './utils/linkList.js';

package.json

@@ -1,4 +1,5 @@
 {
+  "type": "module",
   "name": "algorithm",
   "version": "1.0.0",
   "description": "数据结构算法（javascript描述）",

utils/linkList.js

@@ -0,0 +1,120 @@
+/**
+ * 查找链表最后一个元素
+ * @param { ListNode } root 
+ * @returns 
+ */
+export const findLinkEnd = (root) => {
+    if (root.next == null) return root;
+    return findLinkEnd(root.next)
+}
+/**
+ * 通过类数组索引找到当前元素
+ * @param {*} root 
+ * @param {*} index 
+ * @returns 
+ */
+export const findLinkItemByIndex = (root, index) => {
+    let i = 0;
+    while (root != null) {
+        if (i == index) {
+            return root
+        }
+        i++
+        root = root.next
+    }
+    return null
+}
+/**
+ * 遍历
+ * @param {*} root 
+ */
+export const bianli = (root) => {
+    while (root !== null) {
+        console.log(root.val)
+        root = root.next
+    }
+}
+/**
+ * 判断链表是否有换
+ * @param {*} root 
+ * @returns 
+ */
+export const isCircularLinkList = (root) => {
+    let low = root;
+    let quick = root;
+    while(quick !== null ){
+        if(quick == low) {
+            return true
+        }
+        low = low.next
+        quick = quick.next.next
+    }
+    return false
+}
+
+/** 迭代法
+ * @param {ListNode} l1
+ * @param {ListNode} l2
+ * @return {ListNode}
+ */
+ var mergeTwoLists = function (l1, l2) {
+    let res = new ListNode();
+    let root = res
+    while (l1 !== null && l2 !== null) {
+        if (l1.val <= l2.val) {
+            root.next = l1;
+            l1 = l1.next;
+        } else {
+            root.next = l2
+            l2 = l2.next;
+        }
+        root = root.next
+    }
+    if (l1 != null) {
+        root.next = l1;
+    }
+
+    if (l2 != null) {
+        root.next = l2;
+    }
+    return res.next
+};
+
+/**转化数组法
+ * @param {ListNode} l1
+ * @param {ListNode} l2
+ * @return {ListNode}
+ */
+var mergeTwoLists2 = function (l1, l2) {
+    if (l1 == null && l2 == null) return l1
+    const l1res = bianli(l1)
+    const l2res = bianli(l2)
+    const resData = [...l1res, ...l2res].sort((a, b) => a - b)
+    let root = new ListNode(resData[0]);
+    let res = root;
+    for (let i = 1; i < resData.length; i++) {
+        res.next = new ListNode(resData[i])
+        res = res.next;
+    }
+    return root
+};
+
+
+/**递归
+ * @param {ListNode} l1
+ * @param {ListNode} l2
+ * @return {ListNode}
+ */
+var mergeTwoLists3 = function (l1, l2) {
+    if (l1 == null) {
+        return l2;
+    } else if (l2 == null) {
+        return l1;
+    } else if (l1.val < l2.val) {
+        l1.next = mergeTwoLists(l1.next, l2);
+        return l1;
+    } else {
+        l2.next = mergeTwoLists(l1, l2.next);
+        return l2;
+    }
+};

链表/myLinkList.js

@@ -0,0 +1,52 @@
+import { bianli, findLinkEnd, findLinkItemByIndex } from "../utils/linkList.js"
+
+class ListNode {
+    val = null
+    next = null
+    constructor(val = null) {
+        this.val = val
+    }
+}
+
+class LinkList {
+    root = null
+    constructor(root) {
+        if (root instanceof ListNode) {
+            this.root = root
+        } else {
+            this.root = new ListNode()
+        }
+    }
+    add(item) {
+        if (item instanceof ListNode) {
+            const rootEnd = findLinkEnd(this.root)
+            rootEnd.next = item
+            return rootEnd.next
+        }
+        throw new Error("传入元素不匹配")
+    }
+    remove(index) {
+        if(typeof index !== "number") throw new Error("类型错误")
+        const curr = findLinkItemByIndex(this.root, index - 1);
+        if(curr == null || curr.next == null ){
+            console.log("长度越界")
+            return
+        }
+        const newNext = curr.next.next;
+        curr.next = newNext
+    }
+
+}
+
+const link = new LinkList()
+link.root.val = 1
+link.add(new ListNode(2))
+link.add(new ListNode(3))
+link.add(new ListNode(4))
+
+link.remove(2)
+// console.log(link)
+
+// bianli(link.root)
+// console.log( findLinkEnd(link.root))
+// console.log( findLinkItemByIndex(link.root, 4) )