Problem 1: Write a regular expression that recognizes the following language over the alphabet {a,b}: Any string containing the letters a and b, where the number of letters is not a multiple of three. (Note that 0 is a multiple of three.) Your regular expression should contain only a and b, and the metacharacters (, ), *, +, ? and |. Problem 2: Write a context free grammar that recognizes language from Problem 1. Your start symbol should be named S.

Problem 1: Write a regular expression that recognizes the following language over the alphabet {a,b}: Any string containing the letters a and b, where the number of letters is not a multiple of three. (Note that 0 is a multiple of three.) Your regular expression should contain only a and b, and the metacharacters (, ), *, +, ? and |. Problem 2: Write a context free grammar that recognizes language from Problem 1. Your start symbol should be named S.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Give context free grammar for the following :
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