I think I'm missing something as well. My logic follows yours, and I got *almost* the same answers (in my head, anyway) as dws'. Ours differ firstly because he repeated 1111 ;), but more importantly on the number 101. I can't see that number matching, as 1(01*0)*1 as far as I can tell would match 1, then choosing to continue into the middle group, it would at the very least match 00, not? The only quantifier is on the 1, so as I see it, 00 needs to be matched, then the final 1, so that choosing to include the middle group would yield at minimum 1001. Thusly, I came up with:
""
0
00
11
000
0000
1001
1111
00000
10101

[download]
Yet, I know that's not right (in hindsight). After looking over some other answers, I tried out 0011, 1100 and 0110, which all work out in practice, yet I can't figure out why. Is there some precedence issue that I'm missing?
Eh..I've got some time to figure it out though, I'm only a 3rd year undergrad ;)

In reply to Re: Re: Re: Regex refresher (help?) by charnos
in thread Regex refresher by FoxtrotUniform

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