二刷148

Author: diguage

Diff for: docs/0148-sort-list.adoc

@@ -1,32 +1,65 @@
 [#0148-sort-list]
-= 148. Sort List
+= 148. 排序链表
 
-{leetcode}/problems/sort-list/[LeetCode - Sort List^]
+https://leetcode.cn/problems/sort-list/[LeetCode - 148. 排序链表 ^]
 
-Sort a linked list in _O_(_n_ log _n_) time using constant space complexity.
+给你链表的头结点 `head` ，请将其按 *升序* 排列并返回 *排序后的链表* 。
 
-*Example 1:*
+*示例 1：*
 
-[subs="verbatim,quotes,macros"]
-----
-*Input:* 4->2->1->3
-*Output:* 1->2->3->4
+image::images/0148-01.jpg[{image_attr}]
 
-----
+....
+输入：head = [4,2,1,3]
+输出：[1,2,3,4]
+....
 
-*Example 2:*
+*示例 2：*
 
-[subs="verbatim,quotes,macros"]
-----
-*Input:* -1->5->3->4->0
-*Output:* -1->0->3->4->5
-----
+image::images/0148-02.jpg[{image_attr}]
+
+....
+输入：head = [-1,5,3,4,0]
+输出：[-1,0,3,4,5]
+....
+
+*示例 3：*
+
+....
+输入：head = []
+输出：[]
+....
 
+*提示：*
 
+* 链表中节点的数目在范围 `[0, 5 * 10^4^]` 内
+* `-10^5^ \<= Node.val \<= 10^5^`
+
+**进阶：**你可以在 stem:[O(n*logn)] 时间复杂度和常数级空间复杂度下，对链表进行排序吗？
+
+== 思路分析
 
 [[src-0148]]
+[tabs]
+====
+一刷::
++
+--
 [{java_src_attr}]
 ----
 include::{sourcedir}/_0148_SortList.java[tag=answer]
 ----
+--
+
+二刷::
++
+--
+[{java_src_attr}]
+----
+include::{sourcedir}/_0148_SortList_2.java[tag=answer]
+----
+--
+====
+
+== 参考资料
 

Diff for: docs/images/0148-01.jpg

@@ -190,6 +190,11 @@ endif::[]
 |{doc_base_url}/0050-powx-n.adoc[题解]
 |✅ 递归很简单，抽空再思考一下非递归形式。
 
+|{counter:codes2503}
+|{leetcode_base_url}/sort-list/[148. 排序链表]
+|{doc_base_url}/0148-sort-list.adoc[题解]
+|✅ 分治
+
 |===
 
 截止目前，本轮练习一共完成 {codes2503} 道题。

Diff for: docs/images/0148-02.jpg

@@ -39,6 +39,9 @@ public class _0148_SortList {
      * Runtime: 4 ms, faster than 62.99% of Java online submissions for Sort List.
      *
      * Memory Usage: 40.2 MB, less than 89.47% of Java online submissions for Sort List.
+     *
+     * @author D瓜哥 · https://www.diguage.com
+     * @since 2019-10-29 21:05
      */
     public ListNode sortList(ListNode head) {
         if (Objects.isNull(head) || Objects.isNull(head.next)) {

Diff for: logbook/202503.adoc

@@ -0,0 +1,59 @@
+package com.diguage.algo.leetcode;
+
+import com.diguage.algo.util.ListNode;
+import com.diguage.util.ListNodes;
+
+import java.util.Arrays;
+
+public class _0148_SortList_2 {
+  // tag::answer[]
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2025-04-08 15:06:31
+   */
+  public ListNode sortList(ListNode head) {
+    if (head == null || head.next == null) {
+      return head;
+    }
+    // 分
+    ListNode pre = head, slow = head, fast = head;
+    while (fast != null && fast.next != null) {
+      pre = slow;
+      slow = slow.next;
+      fast = fast.next.next;
+    }
+    pre.next = null; // 将链表切成两段
+    // 治
+    ListNode r1 = sortList(head);
+    ListNode r2 = sortList(slow);
+    // 合
+    return merge(r1, r2);
+  }
+
+  private ListNode merge(ListNode l1, ListNode l2) {
+    ListNode result = new ListNode(0);
+    ListNode cur = result;
+    while (l1 != null && l2 != null) {
+      if (l1.val <= l2.val) {
+        cur.next = l1;
+        l1 = l1.next;
+      } else {
+        cur.next = l2;
+        l2 = l2.next;
+      }
+      cur = cur.next;
+    }
+    if (l1 != null) {
+      cur.next = l1;
+    }
+    if (l2 != null) {
+      cur.next = l2;
+    }
+    return result.next;
+  }
+  // end::answer[]
+
+  public static void main(String[] args) {
+    new _0148_SortList_2().sortList(ListNodes.build(Arrays.asList(4, 2, 1, 3)));
+  }
+}