YoungForest's blog

RankNameScoreFinish TimeQ1 (3)Q2 (4)Q3 (5)Q4 (6)179 / 3745YoungForest180:41:100:02:390:10:360:12:530:36:10 1This was my first biweekly contest after returning to China. My hands were a bit rusty, and my form was still recovering. Recently, because of the novel coronavirus epidemic, I have been isola

This week my glasses broke, so I was not in form. Dinner at home was also late, so I did not finish the problems. RankNameScoreFinish TimeQ1 (3)Q2 (4)Q3 (5)Q4 (6)1378 / 7826YoungForest70:11:410:06:510:11:41nullnull1346. Check If N and Its Double Exist Use a HashMap to store the numbers seen before.

RankNameScoreFinish TimeQ1 (3)Q2 (4)Q3 (5)Q4 (6)459 / 6997YoungForest181:04:520:15:310:21:580:41:22 20:54:52I finally returned to my dear motherland. I can get up on Sunday morning to play LeetCode contests again. I have to admit that after four months away, I became much rustier. The ranking says i

This started from a LeetCode problem: 1286. Iterator for Combination. The most perfect implementation would use a Generator, namely Python’s yield. But I did not know how to do that, so I only implemented a solution that precomputes everything and stores the results. It was not elegant. After the co

The root of the problem is that a classmate asked about a lucky number problem: Codeforces 280B. Codeforces 281D is the same problem. Find all unique pairs of maximum and second maximum elements over all sub-arrays in O(NlogN) A lucky number is defined as the XOR value of the maximum and second ma

I did not go out this week, and happened to run into the biweekly contest. It had been a long time since I joined one, so it really felt rare. All the problems in this biweekly contest were standard and not hard. I finished everything with one AC on each problem and still had 50 minutes left. A typi

This semester I was lucky enough to come to Belgium as an exchange student for one semester. I ran into quite a few difficulties around “money”, and gradually worked through them with help from classmates. Here I want to thank the friends who helped me, and also share my own experience so that more

Because Europe was on winter time, I was in UTC +1.00, so for this contest I deliberately got up at 6 a.m. to participate. After finishing, I rested for an hour, then went to Ghent with friends for the whole day. When I came back at night, I suddenly remembered that Machine Learning assignment 2 was

Using macOS does have some inconvenient parts, such as writing to NTFS hard drives or USB drives. By default, Mac only supports reading NTFS. But as long as you have the courage to tinker, the solution is still very simple. Most Recommended Method Mounty for NTFS Pros: free and lightweight. Cons:

1232. Check If It Is a Straight Line Check whether every three consecutive points are collinear. Time complexity: O(N), space complexity: O(1). 1 2 3 4 5 6 7 8 9 10 11 12 13 14 class Solution { bool right(const vector& p1, const vector& p2, const vector& p3) { return (

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