#abc263h. [abc263_h]Intersection 2

[abc263_h]Intersection 2

Problem Statement

There are NN lines in a two-dimensional plane. The ii-th line is Aix+Biy+Ci=0A_i x + B_i y + C_i = 0. It is guaranteed that no two of the lines are parallel.

In this plane, there are fracN(N1)2\\frac{N(N-1)}{2} intersection points of two lines, including duplicates. Print the distance between the origin and the KK-th nearest point to the origin among these fracN(N1)2\\frac{N(N-1)}{2} points.

Constraints

  • 2leNle5times1042 \\le N \\le 5 \\times 10^4
  • 1leKlefracN(N1)21 \\le K \\le \\frac{N(N-1)}{2}
  • $\-1000 \\le |A_i|,|B_i|,|C_i| \\le 1000(1 \\le i \\le N)$
  • No two of the lines are parallel.
  • Aineq0A_i \\neq 0 or Bineq0(1leileN)B_i \\neq 0(1 \\le i \\le N).
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

NN KK A1A_1 B1B_1 C1C_1 A2A_2 B2B_2 C2C_2 vdots\\vdots ANA_N BNB_N CNC_N

Output

Print a real number representing the answer.

Your output is considered correct when its absolute or relative error from the judge's output is at most 10410^{-4}.


Sample Input 1

3 2
1 1 1
2 1 -3
1 -1 2

Sample Output 1

2.3570226040

Let us call the ii-th line Line ii.

  • The intersection point of Line 11 and Line 22 is (4,5)(4,-5), whose distance to the origin is sqrt41simeq6.4031242374\\sqrt{41} \\simeq 6.4031242374.
  • The intersection point of Line 11 and Line 33 is (frac32,frac12)(\\frac{-3}{2},\\frac{1}{2}), whose distance to the origin is fracsqrt102simeq1.5811388300\\frac{\\sqrt{10}}{2} \\simeq 1.5811388300.
  • The intersection point of Line 22 and Line 33 is (frac13,frac73)(\\frac{1}{3},\\frac{7}{3}), whose distance to the origin is frac5sqrt23simeq2.3570226040\\frac{5\\sqrt{2}}{3} \\simeq 2.3570226040.

Therefore, the second nearest intersection point is (frac13,frac73)(\\frac{1}{3},\\frac{7}{3}), and frac5sqrt23\\frac{5\\sqrt{2}}{3} should be printed.


Sample Input 2

6 7
5 1 9
4 4 -3
8 -1 2
0 1 -8
4 0 -4
2 -3 0

Sample Output 2

4.0126752298