## Description:

The country of jiuye composed by N cites. Each city can be viewed as a point in a two- dimensional plane with integer coordinates (x,y). The distance between city i and city j is defined by d

_{ij} = |x

_{i} - x

_{j}| + |y

_{i} - y

_{j}|. jiuye want to setup airport in K cities among N cities. So he need your help to choose these K cities, to minimize the maximum distance to the nearest airport of each city. That is , if we define d

_{i}(1 ≤ i ≤ N ) as the distance from city i to the nearest city with airport. Your aim is to minimize the value max{d

_{i}|1 ≤ i ≤ N }. You just output the minimum.

## Input:

The first line of the input is T (1 ≤ T ≤ 100), which stands for the number of test cases you need to solve.

The first line of each case contains two integers N ,K (1 ≤ N ≤ 60,1 ≤ K ≤ N ),as mentioned above.

The next N lines, each lines contains two integer x

_{i} and y

_{i} (-10

^{9} ≤ x

_{i}, y

_{i} ≤ 10

^{9}), denote the coordinates of city i.

## Output:

For each test case, print a line “Case #t: ”(without quotes, t means the index of the test case) at the beginning. Then a single integer means the minimum.

## Sample Input:

2
3 2
0 0
4 0
5 1
4 2
0 3
1 0
3 0
8 9

## Sample Output:

Case #1: 2
Case #2: 4