AGGRCOW - Aggressive cows

Farmer John has built a new long barn, with N (2 <= N <= 100,000) stalls. The stalls are located along a straight line at positions x1,...,xN (0 <= xi <= 1,000,000,000).

His C (2 <= C <= N) cows don't like this barn layout and become aggressive towards each other once put into a stall. To prevent the cows from hurting each other, FJ wants to assign the cows to the stalls, such that the minimum distance between any two of them is as large as possible. What is the largest minimum distance?


t – the number of test cases, then t test cases follows.
* Line 1: Two space-separated integers: N and C
* Lines 2..N+1: Line i+1 contains an integer stall location, xi


For each test case output one integer: the largest minimum distance.



5 3



Output details:

FJ can put his 3 cows in the stalls at positions 1, 4 and 8,
resulting in a minimum distance of 3.

hide comments
themast3r: 2017-11-01 16:59:04

Possibly the finest problem I solved on SPOJ.

Last edit: 2017-11-01 16:59:18
rebornplusplus: 2017-10-22 10:48:44

Nice problem ;)

jd_tc: 2017-10-20 09:30:44

Thank @grb_avatar for the link, it was really helpful :) :)

edujtm: 2017-10-20 04:50:22

Struggled a lot with this one, hard to define if the binary search is going to give you the result you want. TopCoder helped a lot.

arjun_agrawal: 2017-09-05 06:45:06

Thought this question in a backward manner. Try to search for the answer in a binary search fashion and check its feasibility

pkgleb: 2017-08-27 18:47:35

First, I found solution using Indexed priority queue, but after topcoder's article lecture the solution just show up :)

kspoj: 2017-08-24 20:29:26

Quora helped :)

iket0512: 2017-08-20 07:29:56

Last edit: 2017-08-20 07:30:22
suchith: 2017-08-05 20:00:23

nice problem
thanks to quora thread and top coder tutorial

omaragha: 2017-08-03 16:48:57

Nice BS Problem

Added by:Roman Sol
Time limit:2s
Source limit:10000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Resource:USACO February 2005 Gold Division