1. Let L be the set of strings in fa, b}* that contain an even number of a's and also an even number of b's. Let r = (ablba)(aa|bb) (ab|ba)|(aa|bb))". Show that w e L = w e L(r) by strong induction on Jw. Hint: In the inductive step consider a process of removing pairs of symbols from the front of w.

1. Let L be the set of strings in fa, b}* that contain an even number of a's and also an even number of b's. Let r = (ablba)(aa|bb) (ab|ba)|(aa|bb))". Show that w e L = w e L(r) by strong induction on Jw. Hint: In the inductive step consider a process of removing pairs of symbols from the front of w.

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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