Leetcode Daily

This is the notes for my leetcode daily problems

Day 5 - Jan 5 - 2381. Shifting Letters II

Brute force solution - No

Thoughts

Although I came up with logic for brute force but I was not able to do the shifting of characters forward and backward.

Optimized Solution

Thoughts

The optimized solution uses line sweep algorithm. The algorithm looked simple but I still lack understanding of the problem. Need to learn about it. The character shifting was still tough for me.

Refer link: https://youtu.be/p06jf-QUYQE?si=bIsbOLatZcdZAZVN

Day 6 - Jan 6 - 1769. Minimum Number of Operations to Move All Balls to Each Box

Brute force solution - Yes

Thoughts

This was first time I came up with the solution on my own. I first calculated the number of total boxes and then by iterating through each box I store all the boxes with 1 ball in an arraylist and by | boxesWithball.get(j) - currentbox| we get how many steps we should take to add all the ball to that box.

Although its time complexity is O(n^2), the answer was still accepted. We need to optimize the code.

Optimized solution:

The optimized solution is also pretty simple: We can first calculate the left ball and then the right balls for every box. and then for every box we keep adding all the first and last ball. I did not code this solution since I am busy with applying for jobs but I need to come back later to code the optimized solution.