There are n stacks of n identical-looking coins. All of the coins in one of these stacks are counterfeit, while all the coins in the other stacks are genuine. Every genuine coin weighs 10 grams; every fake weighs 11 grams. You have an analytical scale that can determine the exact weight of any number of coins. a. Devise a brute-force algorithm to identify the stack with the fake coins and determine its worst-case efficiency class. b. Find a constant time algorithm to identify the stack with the fake coins. Hint: It can be done in only one weighting.

There are n stacks of n identical-looking coins. All of the coins in one of these stacks are counterfeit, while all the coins in the other stacks are genuine. Every genuine coin weighs 10 grams; every fake weighs 11 grams. You have an analytical scale that can determine the exact weight of any number of coins. a. Devise a brute-force algorithm to identify the stack with the fake coins and determine its worst-case efficiency class. b. Find a constant time algorithm to identify the stack with the fake coins. Hint: It can be done in only one weighting.

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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