10. Let D = (0 | 1 | 2 | 3 | 4 |... | 9), Z = (1 | 2 | 3 | 4 |... | 9), and L= (A | B | C |... | Z). Using the symbols D, Z and L, write a regular expression that defines each of the following languages: a. () the strings of digits with exactly two zeros 0. b. the set of identifiers composed of letters, digits, and the underscore, that begins with a letter or the underscore character and end with a Digit.

10. Let D = (0 | 1 | 2 | 3 | 4 |... | 9), Z = (1 | 2 | 3 | 4 |... | 9), and L= (A | B | C |... | Z). Using the symbols D, Z and L, write a regular expression that defines each of the following languages: a. () the strings of digits with exactly two zeros 0. b. the set of identifiers composed of letters, digits, and the underscore, that begins with a letter or the underscore character and end with a Digit.

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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