题解 | 牛牛的数学作业
牛牛的数学作业
https://www.nowcoder.com/practice/6f5d239c34a7429cb325a3d836abc342
t=int(input())
for i in range(t):
n=int(input())
ls=list(map(int,input().split()))
avg=sum(ls)/len(ls)
fangcha=0
fangcha_ls=[]
for a in range(len(ls)):
fangcha_ls.append((ls[a]-avg)**2)
f=sum(fangcha_ls)/len(ls)
print(max(ls)-min(ls),f'{f:.3f}')
