# 21.1: Finding a Specific Member of an Array

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## Overview

Finding a specific member of an array means searching the array until the member is found. It's possible that the member does not exist and the programmer must handle that possibility within the logic of his algorithm. Two specific searches can be made for the maximum (largest) values in the array or the minimum (smallest) value in the array. Maximum and minimum are also know as max and min.

There are two basic ways of searching for a specific value:

Linear search

Binary search

"The linear search is a very simple algorithm. Sometimes called a sequential search, it uses a loop to sequentially step through an array, starting with the first element. It compares each element with the value being search for, and stops when either the value is found or the end of the array is encountered. If the value being searched for is not in the array, the algorithm will search to the end of the array."

Binary search is not cover in this module. Linear search and searching for the maximum is demonstrated in the demo file provided, thus you need to study this material in conjunction with the demo program.

## Demonstration Program in C++

#### Creating a Folder or Sub-Folder for Source Code Files

Depending on your compiler/IDE, you should decide where to download and store source code files for processing. Prudence dictates that you create these folders as needed prior to downloading source code files. A suggested sub-folder for the Bloodshed Dev-C++ 5 compiler/IDE might be named:

• Demo_Programs

If you have not done so, please create the folder(s) and/or sub-folder(s) as appropriate.

Download and store the following file(s) to your storage device in the appropriate folder(s). Following the methods of your compiler/IDE, compile and run the program(s). Study the source code file(s) in conjunction with other learning materials. You may need to right click on the link and select "Save Target As" in order to download the file.

## Definitions

Linear Search
Using a loop to sequentially step through an array.
Maximum
Aka max or the largest member of an array.
Minimum
Aka min or the smallest member of an array.

## Footnotes

Tony Gaddis, Judy Walters and Godfrey Muganda, Starting Out with C++ Early Objects Sixth Edition(United States of America: Pearson – Addison Wesley, 2008) 559.

This page titled 21.1: Finding a Specific Member of an Array is shared under a CC BY license and was authored, remixed, and/or curated by Kenneth Leroy Busbee (OpenStax CNX) .