题解 | 小红关鸡

import enum
import sys
from math import inf
from functools import lru_cache
from collections import deque

def solve():
    input = sys.stdin.readline
    n, k = list(map(int, input().split()))
    arr = list(map(int, input().split()))
    # 尽可能多的得到鸡窝数量
    arr.sort()
    res = 0
    i = 0
    for j, x in enumerate(arr):
        
        while x - arr[i] > k:
            i += 1
        res = max(res, j - i +1)
    print(float(res) / n)


if __name__ == "__main__":
    solve()