Problem
Given a sorted linked list, delete all duplicates such that each element appear only once.
For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.
My Solution
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode deleteDuplicates(ListNode head) {
ListNode p, q;
if (head == null || head.next == null) {
return head;
} else {
p = head;
q = head.next;
}
while (q != null) {
if (p.val != q.val) {
p = p.next;
p.val = q.val;
}
q = q.next;
}
p.next = null;
return head;
}
}
Great Solution
public ListNode deleteDuplicates(ListNode head) {
ListNode current = head;
while (current != null && current.next != null) {
if (current.next.val == current.val) {
current.next = current.next.next;
} else {
current = current.next;
}
}
return head;
}
