꿈꾸는공학도

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..

https://leetcode.com/problems/maximum-depth-of-binary-tree/description/Given the root of a binary tree, return its maximum depth.A binary tree's maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node. Example 1:Input: root = [3,9,20,null,null,15,7]Output: 3Example 2:Input: root = [1,null,2]Output: 2 Constraints:The number of nodes in the tre..

https://leetcode.com/problems/the-k-weakest-rows-in-a-matrix/description/You are given an m x n binary matrix mat of 1's (representing soldiers) and 0's (representing civilians). The soldiers are positioned in front of the civilians. That is, all the 1's will appear to the left of all the 0's in each row.A row i is weaker than a row j if one of the following is true:The number of soldiers in row..

https://leetcode.com/problems/car-pooling/description/There is a car with capacity empty seats. The vehicle only drives east (i.e., it cannot turn around and drive west).You are given the integer capacity and an array trips where trips[i] = [numPassengersi, fromi, toi] indicates that the ith trip has numPassengersi passengers and the locations to pick them up and drop them off are fromi and toi ..

https://leetcode.com/problems/last-stone-weight/description/You are given an array of integers stones where stones[i] is the weight of the ith stone.We are playing a game with the stones. On each turn, we choose the heaviest two stones and smash them together. Suppose the heaviest two stones have weights x and y with x If x == y, both stones are destroyed, andIf x != y, the stone of weight x is ..

Python / C / C++에서 Array / Linked List 기반으로 heap 구조를 만들어보겠다. Skeleton Code는 GPT를 참고했으며, Min/Max heap은 사실 한 끝 차이라 이 둘을 그냥 번갈아가면서 구현해보기로 한다. 1. Python - Array - Min heapclass PriorityQueueArray: def __init__(self, is_min=True): self.heap = [] self.is_min = is_min # True for min-heap, False for max-heap def parent(self, i): return (i - 1) // 2 def left_child(self, i):..

Given an array of meeting time intervals intervals where intervals[i] = [starti, endi], return the minimum number of conference rooms required.입출력 예시Example 1:Input: intervals = [[0,30],[5,10],[15,20]]Output: 2Example 2:Input: intervals = [[7,10],[2,4]]Output: 1제약사항1  Leetcode의 meeting room #2 문제이다. 문제확인을 위해 유료결제가 필요하지만 그냥 구글링해서 문제를 긁어왔다. 실습시간에도 사용된 문제이니 함 풀어보자   1. C++쉬운 줄 알고 아래처럼 풀었는데,쉽지 않았다....

https://leetcode.com/problems/implement-queue-using-stacks/description/Implement a first in first out (FIFO) queue using only two stacks. The implemented queue should support all the functions of a normal queue (push, peek, pop, and empty).Implement the MyQueue class:void push(int x) Pushes element x to the back of the queue.int pop() Removes the element from the front of the queue and returns i..

https://leetcode.com/problems/battleships-in-a-board/description/Given an m x n matrix board where each cell is a battleship 'X' or empty '.', return the number of the battleships on board.Battleships can only be placed horizontally or vertically on board. In other words, they can only be made of the shape 1 x k (1 row, k columns) or k x 1 (k rows, 1 column), where k can be of any size. At least..

https://leetcode.com/problems/largest-number/description/Given a list of non-negative integers nums, arrange them such that they form the largest number and return it.Since the result may be very large, so you need to return a string instead of an integer. Example 1:Input: nums = [10,2]Output: "210"Example 2:Input: nums = [3,30,34,5,9]Output: "9534330" Constraints:1 0 문제 자체는 일단 설명이 짧아서 좋다. 한 번 D..