P2849 [USACO14DEC] Marathon S

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

The first line gives the values of N and K. The next N lines each contain two space-separated integers, x and y,representing a checkpoint (-1000

Output the minimum distance that Bessie can run by skipping up to K checkpoints. In the sample case shown here, skipping the checkpoints at (8, 3) and (10, -5) leads to the minimum total distance of 4.