The basic task is simple: given N real numbers, you are supposed to calculate their average. But what makes it complicated is that some of the input numbers might not be legal. A legalinput is a real number in [−1000,1000] and is accurate up to no more than 2 decimal places. When you calculate the average, those illegal numbers must not be counted in.
Each input file contains one test case. For each case, the first line gives a positive integer N (≤100). Then N numbers are given in the next line, separated by one space.
For each illegal input number, print in a line ERROR: X is not a legal number where X is the input. Then finally print in a line the result: The average of K numbers is Y where K is the number of legal inputs and Y is their average, accurate to 2 decimal places. In case the average cannot be calculated, output Undefined instead of Y. In case K is only 1, output The average of 1 number is Y instead.
Sample Input 1:
7 5 -3.2 aaa 9999 2.3.4 7.123 2.35
Sample Output 1:
1 2 3 4 5
ERROR: aaa is not a legal number ERROR: 9999 is not a legal number ERROR: 2.3.4 is not a legal number ERROR: 7.123 is not a legal number The average of 3 numbers is 1.38
Sample Input 2:
2 aaa -9999
Sample Output 2:
1 2 3
ERROR: aaa is not a legal number ERROR: -9999 is not a legal number The average of 0 numbers is Undefined
defcheck(string): if all([i in"-1234567890."for i in string]): if ((string.count(".") == 0) or ( string.count(".") == 1and len(string) - string.index(".") <= 3)) and-1000 <= float(string) <= 1000: returnTrue returnFalse
n = int(input()) nums = input().split() ans =  for i in nums: if check(i): ans.append(float(i)) else: print("ERROR: %s is not a legal number" % i) if len(ans) == 0: print("The average of 0 numbers is Undefined") elif len(ans) == 1: print("The average of 1 number is %.2f" % float(ans)) else: print("The average of %d numbers is %.2f" % (len(ans), sum(ans) / len(ans)))