Leetcode 82.Remove duplicates from Sorted List II (delete sort list repeat II) thinking and method of solving problems

Given a sorted linked list, delete all nodes that has duplicate numbers, leaving only distinct numbers from the Original list.

For example,
Given1->2->3->3->4->4->5, return1->2->5.
Given1->1->1->2->3, return2->3.

Idea: This question in just start to do when thinking of a bit, how can not be solved correctly. Rewrite all of the code to remove it later. The idea is to record the current node P=head, then head down, and when the head value is not equal to the value of Head.next, it ends. Compare P==head, equal description not repeated, connected. The inequality indicates that there are repeated, skipping on it can be.

Detailed code such as the following:

/** * Definition for singly-linked list. * public class ListNode {*     int val; *     ListNode Next; *     listnode (int x) {val = x;}}} */public class Soluti On {public    ListNode deleteduplicates (ListNode head) {        ListNode first = new ListNode (0);        ListNode last = first;                ListNode p = head;                while (head = null) {        while (head.next! = null) {//p does not move, head moves back until Head.next and p are unequal        if (p.val = = head.next.val) {        Head = head.next;//equal loop        }else{        break;//Not Equal end        }        if (p = = head) {//Only one        Last.next = p;/ /Join Last        = Last.next;        }        p = head = head.next;//There are multiple then do not join        last.next = null;//Remove association        }return first.next;}    }

Leetcode 82.Remove duplicates from Sorted List II (delete sort list repeat II) thinking and method of solving problems