用python来解PAT乙级1054求平均值-20-满分

这题主要在于分辨是不是符合要求的数，这个用异常处理可以简单达到

题目简单就直接上代码了：

n = int(input())
x = list(input().split())
num = 0
m = 0
for i in x:
    try:
        j = float(i)
        if -1000 <= j <= 1000 and round(j,2) == j:#在范围内且最多只有两位小数
            num +=j
            m +=1
        else:
            print('ERROR: '+str(i)+' is not a legal number')
    except:
        print('ERROR: ' + str(i) + ' is not a legal number')
if m == 0:
    print('The average of 0 numbers is Undefined')
else:
    num = num / m
    if m == 1:
        print('The average of ' + str(m) + ' number is ', end='')
        print('%.2f' % (num))
    else:
        print('The average of ' + str(m) + ' numbers is ', end='')
        print('%.2f' % (num))

提交截图：