leetcode/RemoveDuplicatesfromSortedListII.java at master · xff2016/leetcode

32 lines (31 loc) · 786 Bytes

/**

* Given a sorted linked list, delete all nodes that have duplicate numbers,

* leaving only distinct numbers from the original list.

* For example, Given 1->2->3->3->4->4->5, return 1->2->5. Given 1->1->1->2->3,

* return 2->3.

public class RemoveDuplicatesfromSortedListII {

public ListNode deleteDuplicates(ListNode head) {

if (head == null)

return head;

ListNode start = new ListNode(0);

start.next = head;

ListNode slow = start;

ListNode fast = head;

while (fast.next != null) {

if (slow.next.val != fast.next.val) {

if (slow.next.next == fast.next) {

slow = slow.next;

} else {

slow.next = fast.next;

}

fast = fast.next;

}

if (slow.next.next != fast.next) {

slow.next = fast.next;

}

return start.next;

}

Provide feedback