GATE CS 2024 Set 1 — Question 61
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Theory of Computation → Finite Automata & Regular Languages → Regular Expressions
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Question
Consider the following two regular expressions over the alphabet :The total number of strings of length less than or equal to 5, which are neither in nor in , is _________
Correct answer
44 to 44
Solution
To find the number of strings of length that are neither in nor in , we first identify the strings in for each length .
Strings in are of the form or .
1.Regular Expression :
Strings in are of the form or .- : (1 string)
- : (2 strings)
- : (2 strings)
- : (2 strings)
- : (2 strings)
- : (2 strings)
Strings in are of the form or .
- : None (0 strings)
- : (2 strings)
- : (2 strings)
- : (2 strings)
- : (2 strings)
- : (2 strings)
- : (1 string)
- : (2 strings)
- : (4 strings)
- : (4 strings)
- : (4 strings)
- : (4 strings)
4.Total strings of length over :
Total = .5.Strings neither in nor in :
Count = Total - .Continue learning with Success Tracker
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