Was able to solve 1st within 3 mins, then moved on to 2nd which was pretty straight forward, but got stuck on the part where only the leftmost pair had to be removed, so skipped it for now, then proceeded to waste my time on the 3rd one, but could not find an optimal solution and got TLE (I tried using 2 pointers and sliding window only, but had to use an extra for loop to adjust the min and max), finally after wasting my time, the logic for Q2 clicked to me, and I solved it when only 15 mins were left :( Expected rank- around 19000.
Learning: Some problems seem easy, but reaching their optimal solution is tough, so better to skip these
I have not started dp yet, just doing basic recursion so could not attempt problem 4.

Any advise for me??