Define the term alphabet, prefix and suffix of string, concatenation and Kleen closure with example.

This answer is restricted. Please login to view the answer of this question.

Login Now

Alphabet:

An alphabet is a finite non-empty set of symbols. The symbols can be the letters such as {a, b, c}, bits {0, 1} digits {0, 1, 2 … 9}, common characters like $, #, * etc

For example:

Σ = {0, 1} → Binary alphabets

Σ = {+, -, *} → Special symbols

Prefix of String:

A string is called a prefix of a string w if it is obtained by remaining zero or more trailing symbols of w.

For example:

w = abcd

s = abc is the prefix of w

s is the proper prefix if sw

Suffix of String:

A string is called a suffix of a string w if it is obtained by remaining zero or more leading symbols in w.

For example:

w = abcd

s = bcd is the suffix of w

s is the proper suffix if sw

Concatenation of Strings:

If x and y are two strings over an alphabet, concatenation of x and y is written xy and x consists of the symbols of x followed by those of y.

For example:

x = aaa

y = bbb

xy = aaabbb

yx = bbbaaa

Kleen Closure:

The set of all strings over an alphabet Σ is called Kleen closure of Σ and is denoted by Σ*, Thus Kleen closure is set of all strings over alphabet Σ length 0 or more.

Σ* = Σ0 U Σ1 U Σ2 U Σ3 . . .

E.g: A = {0}

A* = \(\left \{ \frac{0^n}{n = 0, 1, 2 . . .} \right \}\)

If you found any type of error on the answer then please mention on the comment or report an answer or submit your new answer.
Leave your Answer:

Click here to submit your answer.

Discussion
0 Comments
  Loading . . .