Segment Tree is a powerful data structure for range query problems.
Read full report: https://docs.google.com/document/d/1LCSW_KcGjbcl05l46H-AGJPohGDSWpn5Z3LKi7YoZbM
Slide: https://docs.google.com/presentation/d/1HRlR9BMWiE3mmZPexwctZ-SEzRsi2vBP-wyeDT0vvr0