It's soooooo good! I recommend it too. Gives +500 elo boost ;)

This helps. Thank you!

I was already answered by one of the comments above. Thank you!

Hi, I don't quite understand the thought process in D: How do we know the function is monotonous (and what function i.e. whats the argument)? Why is that obvious from the data given by the tutorial that we need to switch the minimum? Also, shouldn't the last index that is less than a_{k_{j}} be a_{k_{j+1}-1} and not a_{k_{j+1}} by its definition? Would appreciate the help.