添加第65题

Author: SherlockUnknowEn

60-69/65. Remove Duplicates from Sorted List(Easy)/83.remove-duplicates-from-sorted-list.cpp

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+/*
+ * @lc app=leetcode id=83 lang=cpp
+ *
+ * [83] Remove Duplicates from Sorted List
+ */
+
+// @lc code=start
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* deleteDuplicates(ListNode* head) {
+        ListNode *dummy = new ListNode(-999);
+        ListNode *d = dummy;
+        dummy->next = head;
+        ListNode *p = head;
+        while (p != nullptr)
+        {
+            if (d->val != p->val)
+            {
+                d->next = p;
+                d = p;
+            }
+            p = p->next;
+        }
+        d->next = p; // 最后一个重复的节点删除
+        return dummy->next;
+    }
+};
+// @lc code=end
+

60-69/65. Remove Duplicates from Sorted List(Easy)/README.md

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+# 删除链表中的重复元素
+
+#### *Remove Duplicates from Sorted List*
+
+存在一个按升序排列的链表，给你这个链表的头节点 `head` ，请你删除所有重复的元素，使每个元素 **只出现一次** 。
+
+返回同样按升序排列的结果链表。
+
+
+英文题目:
+
+Given the `head` of a sorted linked list, *delete all duplicates such that each element appears only once*. Return *the linked list **sorted** as well*.
+
+
+
+**Constraints:**
+
+- The number of nodes in the list is in the range `[0, 300]`.
+- `-100 <= Node.val <= 100`
+- The list is guaranteed to be **sorted** in ascending order.
+
+**example 1**
+
+![example 1](https://github.com/SherlockUnknowEn/leetcode/blob/master/60-69/65.%20Remove%20Duplicates%20from%20Sorted%20List(Easy)/list1.jpeg)
+
+```
+Input: head = [1,1,2]
+Output: [1,2]
+```
+
+**example 2**
+
+![example 1](https://github.com/SherlockUnknowEn/leetcode/blob/master/60-69/65.%20Remove%20Duplicates%20from%20Sorted%20List(Easy)/list2.jpeg)
+
+```
+Input: head = [1,1,2,3,3]
+Output: [1,2,3]
+```
+
+
+
+---
+
+### 思路
+
+1. `d`指针指向第一个元素，`p`指针遍历链表，过程中有
+2. 当`p->val == d->val`时，表明遇到了相同值，`d`不动，`p`继续遍历
+3. 当`p->val != d->val`时，令`d->next = p; d = d->next;`
+4. 注意处理最后一个重复节点即可
+
+
+### 代码
+```cpp
+
+/*
+ * @lc app=leetcode id=83 lang=cpp
+ *
+ * [83] Remove Duplicates from Sorted List
+ */
+
+// @lc code=start
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* deleteDuplicates(ListNode* head) {
+        ListNode *dummy = new ListNode(-999);
+        ListNode *d = dummy;
+        dummy->next = head;
+        ListNode *p = head;
+        while (p != nullptr)
+        {
+            if (d->val != p->val)
+            {
+                d->next = p;
+                d = p;
+            }
+            p = p->next;
+        }
+        d->next = p; // 最后一个重复的节点删除
+        return dummy->next;
+    }
+};
+// @lc code=end
+
+```
+
+本题以及其它leetcode题目代码github地址: [github地址](https:github.com/SherlockUnknowEn/leetcode)

60-69/65. Remove Duplicates from Sorted List(Easy)/list1.jpeg

@@ -64,3 +64,5 @@
 
 ##### 64. [92.Reverse Linked List II](https://github.com/SherlockUnknowEn/leetcode/tree/master/60-69/64.%20Reverse%20Linked%20List%20II(Medium)) 反转链表 II
 
+##### 65. [83.Remove Duplicates from Sorted List](https://github.com/SherlockUnknowEn/leetcode/tree/master/60-69/65.%20Remove%20Duplicates%20from%20Sorted%20List(Easy)) 删除排序链表中的重复元素
+