Given a sorted linked list, delete all duplicates such that each element appear only once.
Example 1:
Input: 1->1->2 Output: 1->2
Example 2:
Input: 1->1->2->3->3 Output: 1->2->3
去除重复的数据：
public ListNode deleteDuplicates(ListNode head) {
if(head == null) {
return head;
}
ListNode tmp = head;
ListNode next = head.next;
while(next!=null) {
if(tmp.val == next.val) {
next = next.next;
}else {
tmp.next = next;
tmp = tmp.next;
next = next.next;
}
}
if(tmp!=null) {
tmp.next = next;
}
return head;
}