atcoder#ABC227D. [ABC227D] Project Planning

[ABC227D] Project Planning

Score : 400400 points

Problem Statement

KEYENCE has NN departments, where AiA_i employees belong to the ii-th department (1iN)(1 \leq i \leq N). No employee belongs to multiple departments.

The company is planning cross-departmental projects. Each project will be composed of exactly KK employees chosen from KK distinct departments.

At most how many projects can be made? No employee can participate in multiple projects.

Constraints

  • 1KN2×1051 \leq K \leq N \leq 2 \times 10^5
  • 1Ai10121 \leq A_i \leq 10^{12}
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

NN KK

A1A_1 A2A_2 \ldots ANA_N

Output

Print the maximum possible number of projects.

3 3
2 3 4
2

There can be two projects, each composed of three employees from distinct departments.

4 2
1 1 3 4
4
4 3
1 1 3 4
2