Differences
This shows you the differences between two versions of the page.
Next revision | Previous revision | ||
lfa:2023:lab08 [2023/12/04 22:12] mihai.udubasa created |
lfa:2023:lab08 [2023/12/08 13:23] (current) alexandra.udrescu01 |
||
---|---|---|---|
Line 19: | Line 19: | ||
**8.1.1.** Show that the pumping lemma holds for finite languages. | **8.1.1.** Show that the pumping lemma holds for finite languages. | ||
- | /* | + | |
<hidden Solution> | <hidden Solution> | ||
Line 29: | Line 29: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.1.2.*** Find a language which is not regular for which the pumping lemma holds. | **8.1.2.*** Find a language which is not regular for which the pumping lemma holds. | ||
Line 40: | Line 40: | ||
- | /* | + | |
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 63: | Line 63: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.2.2.** $ L = \{ \: w \in \{A,B\}^* \: | \: \#_A(w) = \#_B(w) \: \} $ | **8.2.2.** $ L = \{ \: w \in \{A,B\}^* \: | \: \#_A(w) = \#_B(w) \: \} $ | ||
- | /* | + | |
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 90: | Line 90: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.2.3.** $math[L = \{(01)^n(10)^n \mid n > 0 \} ] | **8.2.3.** $math[L = \{(01)^n(10)^n \mid n > 0 \} ] | ||
- | /* | + | |
<hidden Solution> <note> | <hidden Solution> <note> | ||
$ w_n = (01)^n(10)^n $ | $ w_n = (01)^n(10)^n $ | ||
Line 151: | Line 151: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.2.4.** $ L = \{ \: w \in \{A,B\}^* \: | \: \text{w is a palindrome} \: \} $ | **8.2.4.** $ L = \{ \: w \in \{A,B\}^* \: | \: \text{w is a palindrome} \: \} $ | ||
- | /* | ||
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 177: | Line 176: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.2.5.** $ L = \{ \: w \in \{0\}^* \: | \: \text{the length of w is a prime number} \: \} $ | **8.2.5.** $ L = \{ \: w \in \{0\}^* \: | \: \text{the length of w is a prime number} \: \} $ | ||
Line 183: | Line 182: | ||
- | /* | ||
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 206: | Line 204: | ||
</hidden> | </hidden> | ||
- | */ | + | |
Line 212: | Line 210: | ||
- | /* | ||
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 237: | Line 234: | ||
</hidden> | </hidden> | ||
- | */ | + | |
**8.2.7.** $ L = \{ \: ww^R \: | \: w\in \{0,1\}^* \} $ | **8.2.7.** $ L = \{ \: ww^R \: | \: w\in \{0,1\}^* \} $ | ||
- | /* | ||
<hidden Solution> <note> | <hidden Solution> <note> | ||
Line 265: | Line 261: | ||
</hidden> | </hidden> | ||
- | */ | + | |
Line 271: | Line 267: | ||
**8.3.1.** Using the pumping lemma, prove that $ L = \{ \: A^nB^m \: | \: n \neq m \}$ is not a regular language. | **8.3.1.** Using the pumping lemma, prove that $ L = \{ \: A^nB^m \: | \: n \neq m \}$ is not a regular language. | ||
- | /* | + | |
<hidden Solution> | <hidden Solution> | ||
<note> | <note> | ||
Line 285: | Line 281: | ||
</hidden> | </hidden> | ||
- | */ | ||
- | /* | ||
- | ====== Homework ====== | ||
- | **Exercise I** $ L = \{ \: w \in \{0\}^* \: | \: \text{|w| is a power of 2} \: \} $ | ||
- | **Exercise II** Show that $ \text{snd(L)}$ is a closure property for regular languages. | + | ====== Nice to try at home ====== |
+ | |||
+ | **Exercise I** Show that $ \text{snd(L)}$ is a closure property for regular languages. | ||
$ \text{snd(L)} = \{ \: w \: | \: xw \in L \: \text{, for some x such that |x| = |w|} \: \}$ | $ \text{snd(L)} = \{ \: w \: | \: xw \in L \: \text{, for some x such that |x| = |w|} \: \}$ | ||
- | **Exercise III** Prove that $ L = \{ \: A^nB^mC^{n-m} \: | \: n \geq m \geq 0 \: \}$ is not a regular language without using isomorphisms. | + | **Exercise II** Prove that $ L = \{ \: A^nB^mC^{n-m} \: | \: n \geq m \geq 0 \: \}$ is not a regular language without using isomorphisms. |
- | */ |