Ice-Cream#4035
The beach stretches along the seacoast like a narrow strip. At some points of the beach, ice cream stalls are located. One day, not all the ice cream sellers come to work. Distribute the sellers among the ice-cream stalls so that the minimum distance between them is as large as possible. This way, they will interfere less with each other.
The first line contains the number of stalls (2 < n < 10001) and the number of ice cream sellers (1 < k < n) at work. The second line contains positive integers in increasing order — the coordinates of the stalls (coordinates do not exceed 10^9).
Print one number — the minimum distance between the adjacent sellers in the optimal arrangement.
Example 1
Example 2