Problem 3 a) How many strings are there of length 10 over the alphabet (a, b)...
Multiple Choice How many strings of length 12 over the alphabet {a,b,c} have exactly three a's or have exactly three b's or have exactly three c's? (1?).22-3-(3) °(12):22-3-(?) (3) ° (13)-3-(1) QUESTION 20 Multiple Choice How many binary strings of length 12 have exactly six 1's or begin with a 0? ° (62) +211 -(0 ° (12) +201 - 1 ° (6) +211 -(5) ° (12) + 211
Let n be an even number. How many ternary strings (i.e. strings over the alphabet 10, 1,2]) of length n are there in which the only places that zeroes can appear are in the odd-numbered positions?
Problem 3 (Counting binary strings) 20 marks/ Consider all bit strings of length 15. 1. How many begin with 00? 2. How many begin with 00 and end with 11? 3. How many begin with 00 or end with 10? 4. How many have exactly ten 1's? 5. How many have exactly ten 1's such as none of these 1's are adjacent to each other? Provide detailed justifications for your answers.
Problem 3 (Counting binary strings) 20 marks/ Consider all...
(a) Suppose we create strings from the alphabet {a, b}, for example, “baba”, “abab”, or “aaab”. How many strings of length 10 are there that have at least one of each letter in the alphabet? (b) Suppose we change to the alphabet {a, b, c}. Now how many strings of length 10 are there that have at least one of each letter in the alphabet?
(a) Suppose we create strings from the alphabet {a, b}, for example “baba”, “abab”, or “aaab”. How many strings of length 10 are there that have at least one of each letter in the alphabet? (b) Suppose we change to the alphabet {a, b, c}. Now how many strings of length 10 are there that have at least one of each letter in the alphabet?
(5) Describe the strings in the set S of strings over the alphabet Σ = a, b, c defined recursively by (1) c E S and (2) if x є S then za E S and zb є S and cr є S. Hint: Your description should be a sentence that provides an euasy test to check if a given string is in the set or not. An example of such a description is: S consists of all strings of...
Let A be the set of all bit strings of length 10. 1. How many bit strings of length 10 are there? How many bit strings of length 10 begin with 1101? How many bit strings of length 10 have exactly six 0's? How many bit strings of length 10 have equal numbers of O's and 1's? How many bit strings of length 10 have more O's than 1's? a. b. c. d. e.
How many bit strings of length 10 have... (a) Exactly four 1s in a row? (b) at least eight 0s in a row?
Construct an DFA automaton that recognizes the following language of strings over the alphabet {a,b}: the set of all strings over alphabet {a,b} that contain aa, but do not contain aba.
Exercise 8.12.20: Counting binary strings. (a) How many binary strings of length 12 do not have exactly four 1's? (b) How many binary strings of length 12 start with 101 or 1110? (e) How many binary strings of length 12 start with 00 or end with 00 or both?