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CS150 S21 - Shared screen with speaker view
James Ooi
00:19
hello
Sebastian Hall
00:25
Hello everyone
Micah Galos
00:27
afternoon all
Justin Wang
00:31
sup
Aaron Geesink
00:37
hello
Diego Vega
00:43
good evening
Jimmy Im
00:48
hello
Bilal Shafi
09:30
I’ve heard regular expressions can’t capture all languages is this true for FA’s as well
Aaron Geesink
11:24
so is the start also the end here?
Patrick D Fenn
11:55
he just said that it did
Justin Wang
20:46
so how do we check if the states is C or D
Justin Wang
21:20
ohh got it
Thomas Henningson
22:02
How come there is no 001r?
Terrence Wu
22:30
because 001 will go to D
Terrence Wu
22:40
so its 001a
Justin Wang
25:10
last bit is 0?
Rayyaan Mustafa
29:05
does the circle around q0 indicate that it is the final state?
Harris Shepard
29:16
seems straightforward
Justin Wang
29:50
yes
Thomas Henningson
30:04
because you want the empty string to be accepted?
Justin Wang
31:14
empty set shouldn't be divisible by 0, since it is not a binary number, so it cant be a binary number divisible by 2
Justin Wang
31:26
shouldnt be accepted *
Najmeh Arani
33:04
even number of ones?
Justin Wang
33:29
101 isn't divisible by 3
Najmeh Arani
33:53
ahh
Westin Montano
37:01
wow :0
Bilal Shafi
38:09
How do we know there is no transition between q2 and q0
Westin Montano
38:42
So on the homework, when asked to make a DFA, our answer should look something like this?
Bilal Shafi
38:46
thanks
Westin Montano
38:58
thank you!
Jackson Hoke
39:04
do we have to pass in the remainder of the division by 3 to this DFA or does this work for the entire string of binary numbers?
Najmeh Arani
41:18
3 states representing 0, 00, and 000
Justin Wang
42:15
The way to think about the divisible by 3 DFA is every time you add a digit (transition), you are either (multiplying by 2 and adding 0, or multiplying by 2 and adding 1) For example, if u were already divisible by 3, multiplying by 2 will result in a number still divisible by 3.
Jackson Hoke
42:58
@justin thanks that makes sense
Westin Montano
43:10
can they all be final states?
Thomas Henningson
43:14
q0 q1 q2
Justin Wang
43:20
all but q3
Aaron Geesink
48:24
just learn how to make the dense matrix pattern and use that for everything
Aaron Geesink
48:25
ez
Terrence Wu
51:31
so why didnt it?
Justin Wang
53:30
free will
Garrett Geesink
53:37
then how does it know which choice to choose?
Najmeh Arani
57:49
Why it is stuck at the first q2?
James Ooi
58:02
there's no transition
Boning Li
58:09
Cuz there’s a 1 after that
Garrett Geesink
58:28
because we feed it another 0 after the first q2, but it cannot move from q2 to anywhere else
Heidi Dye
58:54
Because you read it 001 and you have a 01 leftover but there are no transitions for 0
Justin Wang
58:56
if we wanted to, we could make a DFA for the same problem right
Najmeh Arani
59:58
Thanks all
Justin Wang
01:08:41
NFA's at least for this problem remind my of dynamic programming, where we don't know the answer so we try everything
Justin Wang
01:08:46
me*
Aaron Geesink
01:09:29
shouldn't it equal {q0, q2}?
Justin Wang
01:10:20
its {q0, q1} since those are the only two possible transitions based on the first four bits 0010
Justin Wang
01:10:51
when u add the last bit, you check delta(q0,1) and delta (q1,1) to see if either of them yield q2
James Ooi
01:14:23
it looks ok
Najmeh Arani
01:20:55
Is it in the book too?
Westin Montano
01:23:28
Thank you!
Boning Li
01:23:33
What about the proof of DFA?
Harris Shepard
01:23:35
thank you professor
Hridya Antony
01:23:36
Thank you!
Daisy Sanchez
01:23:38
thanks
Gabriel Salazar
01:23:41
thank you
Michael O'Dea
01:23:42
thank you!!
Justin Wang
01:23:45
thank you
Sebastian Hall
01:23:57
Farewell everyone
Yishao Wang Wang
01:26:35
thank you