Round 1:

1. https://leetcode.com/problems/merge-intervals/
   Variation of this problem. Asked to tell the max number of events happening at once on a given day where the intervals denote the start and end day in the month
2. https://leetcode.com/problems/add-two-numbers/

Round 2:

1. https://leetcode.com/problems/spiral-matrix/
2. https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/
   Variation of buy and sell stock where you can hold as many stocks as you wish