def draw_exhibition() -> int:
n, m = map(int, input().split())
#### 转成int后再次转成平方
input_list = list(map(lambda x: int(x) ** 2, input().split()))
min_val = float("inf")
input_list.sort()
start = 0
for end in range(m - 1, n):
### 区间内的平方差,就是最后一个-最前一个
cur_val = input_list[end] - input_list[start]
if cur_val < min_val:
min_val = cur_val
start += 1
print(min_val)
draw_exhibition()

京公网安备 11010502036488号