Marathon timer 1s memory 256MB

Problem 1: Marathon [Nick Wu, 2014]

Unhappy with the poor health of his cows, Farmer John enrolls them in an assortment of different physical fitness activities. His prize cow Bessie is enrolled in a running class, where she is eventually expected to run a marathon through the downtown area of the city near Farmer John's farm!

The marathon course consists of N checkpoints (3 <= N <= 100,000) to be visited in sequence, where checkpoint 1 is the starting location and checkpoint N is the finish. Bessie is supposed to visit all of these checkpoints one by one, but being the lazy cow she is, she decides that she will skip up to one checkpoint in order to shorten her total journey. She cannot skip checkpoints 1 or N, however, since that would be too noticeable.

Please help Bessie find the minimum distance that she has to run if she can skip up to one checkpoint.

Note that since the course is set in a downtown area with a grid of streets, the distance between two checkpoints at locations (x1, y1) and (x2, y2) is given by |x1-x2| + |y1-y2|. This way of measuring distance -- by the difference in x plus the difference in y -- is sometimes known as "Manhattan" distance because it reflects the fact that in a downtown grid, you can travel parallel to the x or y axes, but you cannot travel along a direct line "as the crow flies".