Greedy

My initial approach is to merge the intervals in the points array by calculating their overlapping parts. Each merged interval requires one arrow. Therefore, by counting the number of merged intervals, I can determine the minimum number of arrows needed to burst all balloons.

This is the first time I have joined the Leetcode contest, the problems are not as difficult as I thought before, and quite straightforward. Maybe is just the rookie luck, I guess. I finished 2 of 4 and finished the third problem later.

Greedy + Two Pointers

Greedy, use list.poll get the least number of integer list.

Greedy Greedy Greedy.

Greedy pattern