83. Remove Duplicates from Sorted List

https://leetcode.com/problems/remove-duplicates-from-sorted-list/

Remove Duplicates from Sorted List - LeetCode

 

Node의 목록이 주어졌을 때 중복값을 제거한 리스트를 반환하는 문제다.

 

[C++]

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* deleteDuplicates(ListNode* head) {
        ListNode* prev = nullptr;
        ListNode* node = head;
        while (node)
        {
            if (prev && node->val == prev->val)
            {
                prev->next = node->next;
            }
            else
            {
                prev = node;
            }
            
            node = node->next;
        }
        
        return head;
    }
};

 

 

[Python3]

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def deleteDuplicates(self, head: Optional[ListNode]) -> Optional[ListNode]:
        node = head
        
        while node:
            if node.next and node.val == node.next.val:
                node.next = node.next.next
            else:
                node = node.next
        
        return head