Delete the number of duplicates in the sequence linked list (1) leecode

Given a sorted Linked List, delete all duplicates such that each element appear onlyOnce.

For example,
Given1->1->2, Return1->2.
Given1->1->2->3->3, Return1->2->3.

1/** 2 * definition for singly-linked list. 3 * Public class listnode {4 * int val; 5 * listnode next; 6 * listnode (int x) {7 * val = x; 8 * Next = NULL; 9 *} 10 *} 11 */12 public class solution {13 public listnode deleteduplicates (listnode head) {14 15 if (Head = NULL) return head; 16 if (head. next = NULL) return head; 17 18 listnode pre = head; // Save the pre to delete19 listnode cur = head. next; 20 while (Cur! = NULL) 21 {22 if (cur. val = pre. val) 23 {24 25 pre. next = cur. next; // Delete the cur node 26 cur = cur. next; // process the next node 27 28 29} 30 else31 {32 pre = pre. next; 33 cur = cur. next; 34 35} 36 37 38} 39 40 return head; 41 42 43} 44}