Help required: Check valid number

Question

There's a bug in it. Kindly find it out!
import re

#your code goes here
num = input()

pattern = r"[189][0-9]{7}"

if re.match(pattern, num):
print("Valid")
else:
print("Invalid")

Answer 1

You just need to signify the beginning and end of the match in the pattern.

r"^[189][0-9]{7}quot;
Note you can also use [\d] in place of [0-9] it is the shorthand way.

Answer 2

with 'match' method, you can avoid the starting anchor (^), as 'match' only search from start of string (unlike 'search' method, wich match from everywhere in the string)...

however, end anchor ($) is required to be sure there's nothing after the 8th digit ;)

Answer 3

Thanks visph, it worked.