꿈꾸는공학도

이번 문제는 Linked list를 C 코드로 구현하는 것인데, 특이점은 각 Node가 Stack 구조라는 것이다.즉 아래와 같이 Linked list Node가 존재한다는 것!  다시 말하면, 밖에서 봤을 땐 하나의 커다란 Stack인데 이것들이 내부에선 Linked list로 구성이 되어 있다는 것이다.문제의 조건은 아래와 같다.   1. 각 Stack Node에는 Max-capacity가 존재하다. Max-capacity를 넘어서면 새로운 Stack Node를 만든다.   2. list_size() method를 구현하라. 현재 원소가 존재하는 List Node(stack)의 개수를 반환한다.   3. push() method를 구현하라.   4. pop() method를 구현하라. 원소가 Link..

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..

https://leetcode.com/problems/pancake-sorting/description/Given an array of integers arr, sort the array by performing a series of pancake flips.In one pancake flip we do the following steps:Choose an integer k where 1 Reverse the sub-array arr[0...k-1] (0-indexed).For example, if arr = [3,2,1,4] and we performed a pancake flip choosing k = 3, we reverse the sub-array [3,2,1], so arr = [1,2,3,4]..

https://leetcode.com/problems/minesweeper/description/Let's play the minesweeper game (Wikipedia, online game)!You are given an m x n char matrix board representing the game board where:'M' represents an unrevealed mine,'E' represents an unrevealed empty square,'B' represents a revealed blank square that has no adjacent mines (i.e., above, below, left, right, and all 4 diagonals),digit ('1' to '..

https://leetcode.com/problems/next-greater-element-i/description/The next greater element of some element x in an array is the first greater element that is to the right of x in the same array.You are given two distinct 0-indexed integer arrays nums1 and nums2, where nums1 is a subset of nums2.For each 0  j such that nums1[i] == nums2[j] and determine the next greater element of nums2[j] in nums..

https://leetcode.com/problems/swap-nodes-in-pairs/description/Given a linked list, swap every two adjacent nodes and return its head. You must solve the problem without modifying the values in the list's nodes (i.e., only nodes themselves may be changed.) Example 1:Input: head = [1,2,3,4]Output: [2,1,4,3]Explanation:Example 2:Input: head = []Output: []Example 3:Input: head = [1]Output: [1]Exampl..

C - 2개 / C++ - 2개 이렇게 총 4개의 코딩문제를 3시간에 거쳐서 풀어보았다. 문제는 Time / Space Complexcity를 크게 고려하지 않고, 정답만 도출되면 인정되는 부분이라 어거지로 코드를 짜서 답을 도출해내는 데에는 성공을 했으나.. 앞으로 좀 더 효율적인 코딩을 하기 위해선 Coding Review정도는 하고 넘어가는 것이 좋을 거 같아 글을 적어본다. 문제의 출처도 제공되진 않지만, 시험이 끝나고 내가 스스로 복기 + 구글링/GPT를 이용해서 문제 출처를 추려내어 보았다.  1번 문제https://school.programmers.co.kr/learn/courses/30/lessons/42627 프로그래머스SW개발자를 위한 평가, 교육, 채용까지 Total Solution을..

https://leetcode.com/problems/maximum-difference-between-node-and-ancestor/description/Given the root of a binary tree, find the maximum value v for which there exist different nodes a and b where v = |a.val - b.val| and a is an ancestor of b.A node a is an ancestor of b if either: any child of a is equal to b or any child of a is an ancestor of b. Example 1:Input: root = [8,3,10,1,6,null,14,nul..