2024/8/25 LeetCode Hot100 LinkedList以及8.25的每日一题（不会做）

src/main/java/com/cool/hot100/linkedlist/Num148.java

@@ -0,0 +1,116 @@
+package com.cool.hot100.linkedlist;
+
+import org.junit.Test;
+
+/**
+ * Created with IntelliJ IDEA.
+ *
+ * @Author: Cool
+ * @Date: 2024/08/25/19:42
+ * DayNumber 2
+ * Hard 2
+ */
+public class Num148 {
+
+
+    public ListNode sortList(ListNode head) {
+        if (head == null) {
+            return null;
+        }
+        int length = 0;
+        ListNode node = head;
+        while (node != null) {
+            length++;
+            node = node.next;
+        }
+        ListNode newHead = new ListNode(0, head);
+        for (int subLength = 1; subLength < length; subLength <<= 1) {
+            ListNode pre = newHead;
+            ListNode currentNode = pre.next;
+            while (currentNode != null) {
+
+                ListNode list1 = currentNode;
+                for (int i = 1; i < subLength && currentNode.next != null; i++) {
+                    currentNode = currentNode.next;
+                }
+                ListNode list2 = currentNode.next;
+                currentNode.next = null;
+                currentNode = list2;
+                for (int i = 1; i < subLength && currentNode != null && currentNode.next != null; i++) {
+                    currentNode = currentNode.next;
+                }
+                ListNode next = null;
+                if (currentNode != null) {
+                    next = currentNode.next;
+                    currentNode.next = null;
+                }
+                pre.next= merge(list1, list2);
+               while(pre.next!=null){
+                   pre=pre.next;
+               }
+               currentNode=next;
+            }
+
+        }
+        return newHead.next;
+    }
+
+
+//    public ListNode sortList(ListNode head) {
+//        return sortList(head, null);
+//    }
+
+    //此法为归并排序自顶向下 空间复杂度O(logn)
+    public ListNode sortList(ListNode head, ListNode tail) {
+        if (head == null) {
+            return null;
+        }
+        if (head.next == tail) {
+            head.next = null;
+            return head;
+        }
+        // 快慢指针，将链表分成两部分
+        ListNode slow = head;
+        ListNode fast = head;
+        while (fast != tail) {
+            slow = slow.next;
+            fast = fast.next;
+            if (fast != tail) {
+                fast = fast.next;
+            }
+        }
+        ListNode list1 = sortList(head, slow);
+        ListNode list2 = sortList(slow, fast);
+        return merge(list1, list2);
+    }
+
+    public ListNode merge(ListNode node1, ListNode node2) {
+        ListNode returnNode = new ListNode(0);
+        ListNode temp = returnNode;
+        while (node1 != null && node2 != null) {
+            if (node1.val <= node2.val) {
+                temp.next = node1;
+                node1 = node1.next;
+            } else {
+                temp.next = node2;
+                node2 = node2.next;
+            }
+            temp = temp.next;
+        }
+
+        temp.next = node1 == null ? node2 : node1;
+
+        return returnNode.next;
+    }
+
+    @Test
+    public void test(){
+        ListNode node1=new ListNode(0);
+        ListNode node2=new ListNode(4,node1);
+        ListNode node3=new ListNode(3,node2);
+        ListNode node4=new ListNode(5,node3);
+        ListNode node5=new ListNode(-1,node4);
+        sortList(node5);
+    }
+
+}

src/main/java/com/cool/one_question_per_day/LeetCode20240825.java

@@ -12,17 +12,17 @@ import java.util.Arrays;
  */
 public class LeetCode20240825 {
 
-    public boolean canPartitionKSubsets(int[] nums, int k) {
+//    public boolean canPartitionKSubsets(int[] nums, int k) {
-        int sum = Arrays.stream(nums).sum();
+//        int sum = Arrays.stream(nums).sum();
-        if(sum%k!=0){
+//        if(sum%k!=0){
-            return false;
+//            return false;
-        }
+//        }
-        int average=sum/k;
+//        int average=sum/k;
-        Arrays.sort(nums);
+//        Arrays.sort(nums);
-        int n = nums.length;
+//        int n = nums.length;
-        if (nums[n - 1] > average) {
+//        if (nums[n - 1] > average) {
-            return false;
+//            return false;
-        }
+//        }
-    }
+//    }
 
 }