I've been stuck at this problem for the past 2 days. I came at a DP recurrence DP(i) = 1+DP(i+1)+DP(nextPossibleInterval(i)), where DP(i) represents all possible subsets of classes b/w ith and nth interval(sorted by endTime).
IMO & from what I've been able to see from solutions of other people(inTheProcessOfDebuggingMine) this logic is correct. For some reason I'm getting WA in some testCases that I'm testing myself & while submitting. I've not been able to debug my code and for that any insight into what might be going wrong is highly appreciated. Thanks!
Sample test case:
8 4 9 1 15 2 18 4 5 7 19 14 25 19 20 3 26 -1 Expected Output: 00000017; Actual Output: 00000026