MJay

1161. Maximum Level Sum of a Binary Tree Medium 1289FavoriteShare Given the root of a binary tree, the level of its root is 1, the level of its children is 2, and so on. Return the smallest level X such that the sum of all the values of nodes at level X is maximal. Example 1: Input: [1,7,0,7,-8,null,null] Output: 2 Explanation: Level 1 sum = 1. Level 2 sum = 7 + 0 = 7. Level 3 sum = 7 + -8 = -1...

In a town, there are N people labelled from 1 to N. There is a rumor that one of these people is secretly the town judge. If the town judge exists, then: The town judge trusts nobody. Everybody (except for the town judge) trusts the town judge. There is exactly one person that satisfies properties 1 and 2. You are given trust, an array of pairs trust[i] = [a, b] representing that the person labe..

Given a grid where each entry is only 0 or 1, find the number of corner rectangles. A corner rectangle is 4 distinct 1s on the grid that form an axis-aligned rectangle. Note that only the corners need to have the value 1. Also, all four 1s used must be distinct. Example 1: Input: grid = [[1, 0, 0, 1, 0], [0, 0, 1, 0, 1], [0, 0, 0, 1, 0], [1, 0, 1, 0, 1]] Output: 1 Explanation: There is only one ..

음 블로그를 쓸 여유가 없네. 이럴때나 써야겠다. 오늘 미팅이 취소됬다. 아놔.. 다시 할거나 생각을 해보자

338. Counting Bits Medium 1693120FavoriteShare Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and return them as an array. Example 1: Input: 2 Output: [0,1,1] Example 2: Input: 5 Output: [0,1,1,2,1,2] Follow up: It is very easy to come up with a solution with run time O(n*sizeof(integer)). But can y..

No more than 2 edges -> 2개는 같은 색깔이 될수있다는 뜻이였네 There is a fence with n posts, each post can be painted with one of the k colors. You have to paint all the posts such that no more than two adjacent fence posts have the same color. Return the total number of ways you can paint the fence. Note: n and k are non-negative integers. Example: Input: n = 3, k = 2 Output: 6 Explanation: Take c1 as color 1,..

논문을 이해 70%퍼는 하면서 다 읽었다. 이제 PPT를 만들어 봐야겠다. PPT도 만들고 Proposal도 다시 읽어보고 Automation도 해봐야겠다. 다 해봐야겠다. PPT는 수욜까지는 끝내야 맘이 편할꺼같다. 오늘 낼 해서 끝내자 20장 정도만 하면 되니까 천천히 해보자 이제 낮이니 퀄을 해야할듯

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security system connected and it will automatically contact the police if two adjacent houses were broken into on the same night. Given a list of non-negative integers representing the amount..

70. Climbing Stairs You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top? Note: Given n will be a positive integer. Example 1: Input: 2 Output: 2 Explanation: There are two ways to climb to the top. 1. 1 step + 1 step 2. 2 steps Example 2: Input: 3 Output: 3 Explanation: There are thre..

Given a string s and a string t, check if s is subsequence of t. You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and s is a short string (= 1B, and you want to check one by one to see if T has its subsequence. In this scenario, how would you change your code? Credits: Special thanks to @pbrother for adding thi..