꿈꾸는공학도

https://leetcode.com/problems/target-sum/description/?envType=daily-question&envId=2024-12-26You are given an integer array nums and an integer target.You want to build an expression out of nums by adding one of the symbols '+' and '-' before each integer in nums and then concatenate all the integers.For example, if nums = [2, 1], you can add a '+' before 2 and a '-' before 1 and concatenate the..

https://leetcode.com/problems/find-minimum-diameter-after-merging-two-trees/description/?envType=daily-question&envId=2024-12-24There exist two undirected trees with n and m nodes, numbered from 0 to n - 1 and from 0 to m - 1, respectively. You are given two 2D integer arrays edges1 and edges2 of lengths n - 1 and m - 1, respectively, where edges1[i] = [ai, bi] indicates that there is an edge be..

https://leetcode.com/problems/minimum-number-of-operations-to-sort-a-binary-tree-by-level/description/?envType=daily-question&envId=2024-12-23You are given the root of a binary tree with unique values.In one operation, you can choose any two nodes at the same level and swap their values.Return the minimum number of operations needed to make the values at each level sorted in a strictly increasin..

class Solution: def leftmostBuildingQueries(self, heights: List[int], queries: List[List[int]]) -> List[int]: ans = [] # O(n^2 sol..) for i in range(len(queries)): # low & high are index high = max(queries[i]) low = min(queries[i]) if high == low or heights[high] > heights[low] : ans.append(high) co..

https://leetcode.com/problems/next-permutation/description/A permutation of an array of integers is an arrangement of its members into a sequence or linear order.For example, for arr = [1,2,3], the following are all the permutations of arr: [1,2,3], [1,3,2], [2, 1, 3], [2, 3, 1], [3,1,2], [3,2,1].The next permutation of an array of integers is the next lexicographically greater permutation of it..

문제의 요지와 Skleton code는 아래와 같다."""1. binary tree height 구하라2. binary tree balanced 맞는지 체크3. binary search tree 맞는지 체크4. 두 노드의 common ancestor 모두 구하기5. 두 노드의 lowest common ancestor 구하기"""  일단 문제에 쓰인 저 단어들이 각 무엇을 뜻하는지 부터 체크해보기1. height(T0)트리의 높이 구하기:정의: 트리의 높이는 루트 노드에서 가장 깊은 리프 노드까지의 경로 길이입니다.계산:루트 8의 왼쪽 서브트리의 높이 = 2루트 8의 오른쪽 서브트리의 높이 = 2따라서 전체 높이는 3.2. is_balanced(T0)트리가 균형 잡혔는지 여부:정의: 이진 트리가 균형 잡혔..

https://www.geeksforgeeks.org/problems/remove-loop-in-linked-list/1?page=1&category=Linked%20List&difficulty=Medium,Hard&sortBy=submissions Remove loop in Linked List | Practice | GeeksforGeeksGiven the head of a linked list that may contain a loop.  A loop means that the last node of the linked list is connected back to a node in the same list.  So if the next of the previous node is null. then..

https://leetcode.com/problems/construct-string-with-repeat-limit/description/?envType=daily-question&envId=2024-12-17You are given a string s and an integer repeatLimit. Construct a new string repeatLimitedString using the characters of s such that no letter appears more than repeatLimit times in a row. You do not have to use all characters from s.Return the lexicographically largest repeatLimit..

https://leetcode.com/problems/final-array-state-after-k-multiplication-operations-i/description/?envType=daily-question&envId=2024-12-16You are given an integer array nums, an integer k, and an integer multiplier.You need to perform k operations on nums. In each operation:Find the minimum value x in nums. If there are multiple occurrences of the minimum value, select the one that appears first.R..

https://leetcode.com/problems/move-pieces-to-obtain-a-string/description/?envType=daily-question&envId=2024-12-05You are given two strings start and target, both of length n. Each string consists only of the characters 'L', 'R', and '_' where:The characters 'L' and 'R' represent pieces, where a piece 'L' can move to the left only if there is a blank space directly to its left, and a piece 'R' ca..