Practice Listing Valid Programs (5.2.4) - Countability of the set of all strings over a finite alphabet

Practice: Listing valid programs

Lesson 5.2.4Countability of the set of all strings over a finite alphabet

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9 questions

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Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
What is a finite alphabet? Provide an example.
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Think of a simple set of characters.
Question 2.
Define Π* in your own words.
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Link it with the concept of string formation.
3Question 3.
What does Π* represent?
- Set of all programming languages
- Set of all possible strings from an alphabet
- Set of valid programs
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Remember the definitions regarding finite sets.
4Question 4.
True or False: The set of valid programs is uncountable.
- True
- False
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Reflect on the properties of subsets in mathematics.
Question 5.
Given a finite alphabet {x, y}, list all possible strings of length 3 and state how many such strings exist.
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Consider combinations of each character arranged in different orders.
Question 6.
Create a valid program using a finite alphabet composed of basic arithmetic operations and variables. Explain why your program is valid.
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Use starting and ending keywords with correct syntax.

5 more questions in this section. Enroll free to practise them all.