StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
text
Body
copied!<blockquote> <p>However when I call the insertionsort method it gives me an error stating "invalid method declaration; return type required". Why am i receiving this error?</p> </blockquote> <p>You are calling insertionSort() inside DailyTemperatureList class but outside any method which does not compile. I moved the call into main() method, so that it compiles, see bellow.</p> <blockquote> <p>Also is my print statement correct to print out the original arraylist? How would i update it to print out the sorted arraylist? Or can i print that out from the insertionsort method? </p> </blockquote> <p>Print out the original list before calling insertionSort(), and after sorting it print out the sorted list:</p> <pre><code>System.out.println( "original list:" ); System.out.println( dailytemps.toString() ); insertionSort( dailytemps); System.out.println( "sorted list:" ); </code></pre> <p>Output:</p> <pre><code>original list: [Day of WeekMonTemperature87.1, Day of WeekTueTemperature88.3, Day of WeekWedTemperature81.2, Day of WeekThuTemperature84.0, Day of WeekFriTemperature76.3] sorted list: [Day of WeekFriTemperature76.3, Day of WeekWedTemperature81.2, Day of WeekThuTemperature84.0, Day of WeekMonTemperature87.1, Day of WeekTueTemperature88.3] </code></pre> <p>Corrected DailyTemperatureList class:</p> <pre><code>import java.io.*; import java.util.Collections; import java.util.Scanner; import java.util.ArrayList; public class DailyTemperatureList { public static void main (String [] args) { ArrayList<DailyTemperature> dailytemps = new ArrayList<DailyTemperature>(); dailytemps.add(new DailyTemperature("Mon", 87.1)); dailytemps.add(new DailyTemperature("Tue", 88.3)); dailytemps.add(new DailyTemperature("Wed", 81.2)); dailytemps.add(new DailyTemperature("Thu", 84.0)); dailytemps.add(new DailyTemperature("Fri", 76.3)); System.out.println( "original list:" ); System.out.println( dailytemps.toString() ); insertionSort( dailytemps); System.out.println( "sorted list:" ); System.out.println( dailytemps.toString() ); } //public static <DailyTemperature extends Comparable<? super DailyTemperature>> static void insertionSort(ArrayList<DailyTemperature> dailytemps) { DailyTemperature temp = null; int position = 0; //loop from 2nd element on for (int i = 1; i < dailytemps.size(); i++) { temp = dailytemps.get(i); position = i; while ( 0 < position && temp.compareTo(dailytemps.get(position - 1 )) < 0) { dailytemps.set(position, dailytemps.get(position - 1)); position--; } dailytemps.set(position,temp); } } } </code></pre>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload