hyunkookim 님의 블로그

100. Same Tree # Definition for a binary tree node.# class TreeNode:# def __init__(self, val=0, left=None, right=None):# self.val = val# self.left = left# self.right = rightclass Solution: def getElemets(self, node, stack): if not node: return stack.append('null') stack.append(node.val) self.getElemets(node.left, stack) ..

146. LRU Cache https://youtu.be/7ABFKPK2hD4?si=R9ZwBAdBVxHzBRga # Node 추가 class Node: def __init__(self, key, val): self.key, self.val = key, val self.prev = self.next = Noneclass LRUCache: def __init__(self, capacity: int): self.capacity = capacity self.cache = {} # map key to node # left=LRU, right=most recent self.left, self.right = Node(0, 0), ..

86. Partition List class Solution: def partition(self, head: Optional[ListNode], x: int) -> Optional[ListNode]: """ x 기준값보다, 작은 더미 노드 리스트, 큰 더미 노드 리스트를 만들어서 이어주기 """ # 작은 값 리스트와 큰 값 리스트의 더미 노드 생성 small_dummy = ListNode(0) large_dummy = ListNode(0) # 포인터 초기화 small = small_dummy # 작은 값 리스트의 끝 large = large_dummy # ..

61. Rotate List # Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextclass Solution: def rotateRight(self, head: Optional[ListNode], k: int) -> Optional[ListNode]: if not head or not head.next or k == 0: # 예외 처리: 리스트가 비었거나 노드가 하나인 경우 return head # 1. 리스트 길이 계산 length =..

82. Remove Duplicates from Sorted List II # Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextclass Solution: def deleteDuplicates(self, head: Optional[ListNode]) -> Optional[ListNode]: dummy = ListNode(0, head) left = dummy while left: if left.next and left.next.next ..

19. Remove Nth Node From End of List # Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextclass Solution: def removeNthFromEnd(self, head: Optional[ListNode], n: int) -> Optional[ListNode]: """ 아이디어는. 투 포인터(left, right)를 사용하고 right 포인터는 미리 n 만큼 먼저 shifting 한뒤. left, right 를..

25. Reverse Nodes in k-Group https://youtu.be/1UOPsfP85V4?si=VL2go-L_JkxKBX53 # Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val # 노드의 값# self.next = next # 다음 노드를 가리키는 포인터class Solution: def reverseKGroup(self, head: Optional[ListNode], k: int) -> Optional[ListNode]: # 더미 노드 생성: head 이전에 추가해 리스트 시작점을 쉽게 다룰..

92. Reverse Linked List II GPT 코드# Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextclass Solution: def reverseBetween(self, head: Optional[ListNode], left: int, right: int) -> Optional[ListNode]: # Step 1: Dummy 노드 생성 (head가 바뀌는 경우를 처리하기 위해) dummy = ListNode(0) dummy.next = hea..

138. Copy List with Random Pointer https://youtu.be/5Y2EiZST97Y?si=24I-c_Obsw9-9vYx """# Definition for a Node.class Node: def __init__(self, x: int, next: 'Node' = None, random: 'Node' = None): self.val = int(x) self.next = next self.random = random"""class Solution: def copyRandomList(self, head: 'Optional[Node]') -> 'Optional[Node]': if not head: r..

21. Merge Two Sorted Lists # Definition for singly-linked list.# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextclass Solution: def mergeTwoLists(self, list1: Optional[ListNode], list2: Optional[ListNode]) -> Optional[ListNode]: dummy = ListNode() res = dummy while list1 and list2: v1 = list1...