Remove Duplicates from Sorted List
Leetcode 83. Remove Duplicates from Sorted List
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.
class Solution {
public:
ListNode* deleteDuplicates(ListNode* head) {
ListNode* prev = head;
while (prev) {
if (prev->next && prev->val == prev->next->val)
prev->next = prev->next->next;
else
prev = prev->next;
}
return head;
}
};
Leetcode 82. Remove Duplicates from Sorted List
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.
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* deleteDuplicates(ListNode* head) {
ListNode* prevhead = new ListNode(0);
ListNode* prev = head;
ListNode* point = prevhead;
while (prev) {
if (prev->next && prev->val == prev->next->val)
while (prev->next && prev->val == prev->next->val)
prev = prev->next;
else {
point->next = prev;
point = point ->next;
}
prev = prev->next;
}
point->next = NULL;
return prevhead->next;
}
};