A string w of a's and b's is valid if it satisfies one of the following conditions: • w is the empty string • w = aub for some valid string u • w = uv for some valid strings u and v For example, the string w = aaabbabbaabbab is valid, because w = uv, where u = aaabbabb and v = aabbab. Describe an efficient algorithm to determine whether a given string of a's and b's is valid. Analyze its time and space requirements. (Aim for solving the problem in linear time.) Show how the algorithm works on the above example.

A string w of a's and b's is valid if it satisfies one of the following conditions: • w is the empty string • w = aub for some valid string u • w = uv for some valid strings u and v For example, the string w = aaabbabbaabbab is valid, because w = uv, where u = aaabbabb and v = aabbab. Describe an efficient algorithm to determine whether a given string of a's and b's is valid. Analyze its time and space requirements. (Aim for solving the problem in linear time.) Show how the algorithm works on the above example.

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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