## Regular Expression for no 0 or many triples of 0’s with no 1 or many 1 in the strings

# R.E = (000+1)*

## DFA for R.E = (000+1)*

## Regular Expression for no 0 or many triples of 0’s and many 1 in the strings

**Rule**

All strings having exactly no 0 or many triples of 0’s and many 1 must be accepted and all other strings must be rejected by our Regular Expression.

** **R.E = (000+1)^{+}

**Acceptable Strings**

These strings are part of the given language and must be accepted by our Regular Expression.

- 3 Strings of length 1 = {1, no more strings possible}
- 3 Strings of length 2 = {11, no more strings by the length of 2 possible}
- 3 Strings of length 3 = {000, 111, no more strings possible}
- 3 Strings of length 4 = {0001, 1000, 1111, no more string possible}
- 3 Strings of length 7 = {0000001, 0001000, 1000000, and many more similar strings}
- 3 Strings of length 10 = {0000000001, 0000001000, 0001000000, and many more similar strings }
- 3 Strings of length 15 = {000110001000000, 000100011000111, 000111000111000, and many more similar strings }
- 3 Strings of length 20 = {00000000011000100011, 00000000000000011000, 11000110001000100011, and many more similar strings }
- 3 Strings of length 25 = {0001111000111000111100011, 1110001111000000110000001, 1100011000000000000100011, and many more similar strings }
- Many more similar strings.

**Unacceptable Strings**

These strings are not part of the given language and must be rejected by our Regular Expression.

- 3 Strings of length 1 = {0, no more strings possible}
- 3 Strings of length 2 = {01,10,00}
- 3 Strings of length 3 = {010, 100, 001}
- 3 Strings of length 4 = {0011, 1011, 1100, and many more similar strings }
- 3 Strings of length 7 = {0010101, 1010100, 1001010, and many more similar strings }
- 3 Strings of length 10 = {0010010101, 0010010010, 0010100010, and many more similar strings }
- 3 Strings of length 15 = {000100010100010, 010010110010111, 111010101110010, and many more similar strings }
- 3 Strings of length 20 = {00110001100010011011, 00100010001001101010, 11011001010010100011, and many more similar strings }
- 3 Strings of length 25 = {0011101001110010111100011, 1100111100010001100100001, 1100011000001110001000110, and many more similar strings }
- Many more similar strings.

## Regular Expression for no a or many triples of a’s and many b in the strings

**Rule**

All strings having exactly no a or many triples of a’s and many b must be accepted and all other strings must be rejected by our Regular Expression.

** **R.E = (aaa+b)*

**Acceptable Strings**

These strings are part of the given language and must be accepted by our Regular Expression.

- 3 Strings of length 1 = {b, no more strings possible}
- 3 Strings of length 2 = {bb, no more strings by the length of 2 possible}
- 3 Strings of length 3 = {aaa, bbb, no more strings possible}
- 3 Strings of length 4 = {aaab, baaa, bbbb, no more string possible}
- 3 Strings of length 7 = {aaaaaab, aaabaaa, baaaaaa, and many more similar strings}
- 3 Strings of length 10 = {aaaaaaaaab, aaaaaabaaa, aaabaaaaaa, and many more similar strings }
- 3 Strings of length 15 = {aaabbaaabaaaaaa, aaabaaabbaaabbb, aaabbbaaabbbaaa, and many more similar strings }
- 3 Strings of length 20 = {aaaaaaaaabbaaabaaabb, aaaaaaaaaaaaaaabbaaa, bbaaabbaaabaaabaaabb, and many more similar strings }
- 3 Strings of length 25 = {aaabbbbaaabbbaaabbbbaaabb, bbbaaabbbbaaaaaabbaaaaaab, bbaaabbaaaaaaaaaaaabaaabb, and many more similar strings }
- Many more similar strings.

**Unacceptable Strings**

These strings are not part of the given language and must be rejected by our Regular Expression.

- 3 Strings of length 1 = {a, no more strings possible}
- 3 Strings of length 2 = {ab,ba,aa}
- 3 Strings of length 3 = {aba, baa, aab}
- 3 Strings of length 4 = {aabb, babb, bbaa, and many more similar strings }
- 3 Strings of length 7 = {aababab, bababaa, baababa, and many more similar strings }
- 3 Strings of length 10 = {aabaababab, aabaabaaba, aababaaaba, and many more similar strings }
- 3 Strings of length 15 = {aaabaaababaaaba, abaababbaababbb, bbbabababbbaaba, and many more similar strings }
- 3 Strings of length 20 = {aabbaaabbaaabaabbabb, aabaaabaaabaabbababa, bbabbaababaababaaabb, and many more similar strings }
- 3 Strings of length 25 = {aabbbabaabbbaababbbbaaabb, bbaabbbbaaabaaabbaabaaaab, bbaaabbaaaaabbbaaabaaabba, and many more similar strings }
- Many more similar strings.

## Download Slides Regular Expression -Theory of Automata

Regular Expression for no 0 or many triples of 0s with no 1 or many 1 in the strings

## More Examples of Regular Expression

- Regular Expression for no 0 or many triples of 0’s and many 1 in the strings.
- RegExp for strings of one or many 11 or no 11.
- A regular expression for ending with abb
- A regular expression for all strings having 010 or 101.
- Regular expression for Even Length Strings defined over {a,b}
- Regular Expression for strings having at least one double 0 or double 1.
- Regular Expression of starting with 0 and having multiple even 1’s or no 1.
- Regular Expression for an odd number of 0’s or an odd number of 1’s in the strings.
- Regular Expression for having strings of multiple double 1’s or null.
- Regular Expression (RE) for starting with 0 and ending with 1.
- RE for ending with b and having zero or multiple sets of aa and bb.
- A regular expression of the second last symbol is 1.
- RE for starting with 1 having zero or multiple even 1’s.
- Regular Expression for multiple a’s and multiple b’s.
- RE for exactly single 1 many 0’s |exactly single a many b.
- A regular expression for strings starting with aa and ending with ba.
- A regular expression for the language of all consecutive even length a’s.
- A regular expression for the language of all odd-length strings
- A regular expression for the language of all even length strings but ends with aa.
- A regular expression for the language of an odd number of 1s.
- A regular expression for the language of even length strings starting with a and ending with b in theory of automata.
- A regular expression for the language of all even length strings but starts with a.
- A Regular Expression for the Language of all strings with an even number of 0’s or even number of 1’s.
- A regular expression for the language of all those strings end with abb.
- A regular expression for string having must 010 or 101.
- Regular expression of strings begin with 110

Regular expression of strings begin and end with 110

Regular expression of strings containing exactly three consecutive 1’s. - A Regular Expression of all strings divisible by 4.
- A Regular Expression Strings that does not contain substring 110.

## Tutorial: Regular Expression

A detailed tutorial of the regular expression is here in the link of regular expression tutorial. This page contains the practice questions of regular expressions with solutions.\

**Tutorial covering the topics**

- Give a regular expression.
- Describe the strings of the regular expression.
- write a regular expression.
- create all strings from regular expression.
- Generate all strings from regular expression.
- Extract all strings from regular expression.
- Find all strings from regular expression.
- Examples of regular expression.

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