求助各位巨佬,or2
只有第一个错了

import math  
import decimal

tmp = list(map(int, input().split()))  
n = decimal.Decimal(tmp[0])  
s = decimal.Decimal(tmp[1])  
src = list(map(int, input().split()))  
src.sort()  
average = decimal.Decimal(s/n)  
current_average = decimal.Decimal(s/n)  
ans = decimal.Decimal(0)  

for i in range(int(n)):  
    if src[i] < current_average:  
        s -= src[i]  
        current_average = s/(n-i-1)  
        ans += pow(src[i]-average, 2)  
    else:  
        s -= current_average  
        ans += pow(current_average-average, 2)  
ans = round(math.sqrt(ans/n), 4)  
print(ans)