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![Marzoog AlGhazwi](https://uploads.teamtreehouse.com/production/profile-photos/9715262/micro_IMG_1994.jpg)
Marzoog AlGhazwi
15,796 Pointswhy it work with the '8' but with it didn't ??!
Can any one expline why its working that way !
import re
string = '1234567890'
good_numbers = re.findall(r'''
\d
[^5678]+
''', string, re.X)
1 Answer
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsThe "\d" token matches any digit, so without the "8" you get two pieces, "1234" and then "7890" because it "7" is matched by the "\d".
But when you add "8" to the excluded digits, then "7890" no longer matches, so you get "890" where the "8" matches the "\d":.
A more conventional solution might use just one character class without the "any digit" preceding it.