链表排序

CodingProgrammer · web-flow · commit 9ccc261bbed6 · 2020-11-21T11:50:42.000+08:00
diff --git a/每日一题/147.py b/每日一题/147.py
@@ -0,0 +1,89 @@
+'''
+Descripttion: 对链表进行插入排序
+version: 1
+Author: Jason
+Date: 2020-11-20 10:03:56
+LastEditors: Jason
+LastEditTime: 2020-11-21 07:40:47
+'''
+# Definition for singly-linked list.
+import random
+
+
+def GenerateRandomList(number, size):
+    temp = list()
+    random_legth = random.randint(0, size)
+    current_length = 0
+    while current_length < random_legth:
+        temp.append(random.randint(1, number))
+        current_length += 1
+    return temp
+
+
+class ListNode:
+    def __init__(self, x):
+        self.val = x
+        self.next = None
+
+
+class Solution:
+    def insertionSortList(self, head: ListNode) -> ListNode:
+
+        if not head:
+            return None
+        dummy = ListNode(0)
+        dummy.next = head
+        cur = head
+        while cur and cur.next:
+            if cur.val <= cur.next.val:
+                cur = cur.next
+
+            else:
+                temp = cur.next
+                cur.next = cur.next.next
+                pre = dummy
+
+                while temp.val >= pre.next.val:
+                    pre = pre.next
+                temp.next = pre.next
+                pre.next = temp
+
+        return dummy.next
+
+    def insertionSortList2(self, head: ListNode) -> ListNode:
+        ans = ListNode(float("-inf"))
+
+        while head:
+            next = head.next
+            cur = ans
+            while cur.next and cur.next.val < head.val:
+                cur = cur.next
+            head.next = cur.next
+            cur.next = head
+            head = next
+        return ans.next
+
+
+if __name__ == "__main__":
+    s = Solution()
+    for _ in range(100):
+        nums = GenerateRandomList(20, 10)
+        if len(nums) < 1:
+            continue
+        nodes = [ListNode(each_num) for each_num in nums]
+        sorted_nums = list(sorted(nums))
+        # 连接链表
+        for i in range(len(nodes) - 1):
+            nodes[i].next = nodes[i + 1]
+        res = s.insertionSortList2(nodes[0])
+        insertsort_li = list()
+        cur = res
+        while cur:
+            insertsort_li.append(cur.val)
+            cur = cur.next
+        if insertsort_li != sorted_nums:
+            print("wrong:", nums)
+    print("Done")
+    '''
+
+    '''
diff --git a/每日一题/148.py b/每日一题/148.py
@@ -0,0 +1,112 @@
+'''
+Descripttion: 排序链表
+version: 1
+Author: Jason
+Date: 2020-11-21 08:10:16
+LastEditors: Jason
+LastEditTime: 2020-11-21 11:48:00
+'''
+import random
+
+
+def GenerateRandomList(number, size):
+    temp = list()
+    random_legth = random.randint(0, size)
+    current_length = 0
+    while current_length < random_legth:
+        temp.append(random.randint(1, number))
+        current_length += 1
+    return temp
+
+
+class ListNode:
+    def __init__(self, x):
+        self.val = x
+        self.next = None
+
+
+class Solution:
+    def sortList(self, head: ListNode) -> ListNode:
+        if not head or not head.next:
+            return head
+
+        mid = self.getMid(head)
+        right_head = mid.next
+        mid.next = None
+
+        left = self.sortList(head)
+        right = self.sortList(right_head)
+
+        return self.merge(left, right)
+
+    def getMid(self, head: ListNode) -> ListNode:
+        # 找到中点-slow
+        slow = head
+        fast = head
+        # 通过以下while循环，找到链表的中点-slow
+        while fast.next:
+            if fast.next:
+                fast = fast.next
+            else:
+                break
+            if fast.next:
+                fast = fast.next
+            else:
+                break
+            slow = slow.next
+        return slow
+
+    def merge(self, left_head: ListNode, right_head: ListNode) -> ListNode:
+        left_cur = left_head
+        right_cur = right_head
+        dummy_head = ListNode(float('-inf'))
+        cur = dummy_head
+        while left_cur and right_cur:
+            if left_cur.val < right_cur.val:
+                cur.next = left_cur
+                left_cur = left_cur.next
+            else:
+                cur.next = right_cur
+                right_cur = right_cur.next
+            cur = cur.next
+        cur.next = left_cur if left_cur else right_cur
+        return dummy_head.next
+
+
+if __name__ == "__main__":
+    s = Solution()
+    for _ in range(100):
+        nums = GenerateRandomList(20, 10)
+        if len(nums) < 1:
+            continue
+        nodes = [ListNode(each_num) for each_num in nums]
+        sorted_nums = list(sorted(nums))
+        # 连接链表
+        for i in range(len(nodes) - 1):
+            nodes[i].next = nodes[i + 1]
+        res = s.sortList(nodes[0])
+        insertsort_li = list()
+        cur = res
+        while cur:
+            insertsort_li.append(cur.val)
+            cur = cur.next
+        if insertsort_li != sorted_nums:
+            print("wrong:", nums)
+    print("Done")
+    # li1 = [3, 1, 12, 6, 1, 9, 19, 4, 12]
+    # li2 = [2, 4, 6, 8, 10]
+    # nodes1 = [ListNode(each_num) for each_num in li1]
+    # nodes2 = [ListNode(each_num) for each_num in li2]
+    # # 连接链表
+    # for i in range(len(nodes1) - 1):
+    #     nodes1[i].next = nodes1[i + 1]
+    # for j in range(len(nodes2) - 1):
+    #     nodes2[j].next = nodes2[j + 1]
+    # insertsort_li = list()
+    # res = s.sortList(nodes1[0])
+    # cur = res
+    # while cur:
+    #     insertsort_li.append(cur.val)
+    #     cur = cur.next
+    # if insertsort_li != sorted(li1):
+    #     print("wrong:")
