Sorting Array Of Objects With Strings?
Feb 14, 2015
An array has objects with String firstName, String lastName, int ID, char examType('M' or 'F'), and int score. Every object has both Midterm('M') and Final('F'). The array has to be sorted by the first Midterm- 'M' and immediately followed by the Final ('F') of the same person (object). Im having troubles with coming up with a proper algorithm with gettin the Final- 'F' after Midterm for the same person.
Java Code: public static Exam[] collateExams(Exam[] exams) {
Exam [] r = new Exam[10];
r = exams;
int[] position = new int[10];
int index = 0;
for(int i = 0; i < exams.length; i++)
[Code]...
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Apr 3, 2015
I am working on an assignment where I initially have to take as input a number. That number will be the number of strings the user is going to type. As they are typed, they are to be sorted alphabetically, then printed. It took me a while to get this far, and I am stuck on how to properly invoke the other methods in main. There has to be at least three methods: main, one to do the sorting, and one to print the new array. I'm quite sure there are mistakes in my code, but this is definitely a challenge for me. Here is the code. Keep in mind that the methods being invoked are blank on purpose.
I am not allowed to use the Arrays, Arraylist or Collection class. This is basically to test my ingenuity and to see how arrays actually work.
import java.util.*;
public class Sort_as_Inserted {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter number of elements to be sorted: ");
String element_number = input.nextLine();
[Code] ....
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Apr 8, 2014
I have a school assignment that involves me sorting an array of objects based on one of the class String variables. I am using as the title says a simple selection sort method. The problem I'm having is that when I run the program in debug mode, it never seems to enter the if statement in the inner loop. I would like to say I've tried a number of things to figure it out, but honestly I'm just stumped as to why it's not working.
Here is the code:
public static void sortTransactions(Transaction[] oTransaction){// This is the sorting method, obviously it's not done so it currently just prints to screen.
System.out.println("Successful call to sortTransaction()");
String min = "";
int curInd = 0;
Transaction[] temp = new Transaction[1];
[Code] ....
The output when I check to see if the array is sorted verifies that the array never does get sorted.
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Mar 26, 2014
I can sort strings in a collection by uppercase and then lowercase though I was wondering if there is any way of doing it in reverse, sorting by lowercase then by uppercase.
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Oct 16, 2014
how to sort my text file. So far I have been able to read the text file and print it back out, but I am unsure of how to go about sorting it. Must print the colors (in the order of the rainbow first) and if the colors are the same compare the size (bigger is more important)The values I have to sort are written as such in the text file:
blue 18
blue 10
red 27
yellow 4
public class Rainbow{
private String color;
private int size;
public Rainbow(String color, int size){
this.color = color;
this.size = size;
[code]....
I would know how to sort it if it was supposed to be alphabetical order or there were only numbers, but I can't seem to figure out how to sort it when there are strings and integers
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Aug 25, 2014
I am having an array of strings and i want to find out whether these strings contained in the array contain a similar character or not.For example i am having following strings in the array of string:
aadafbd
dsfgdfbvc
sdfgyub
fhjgbjhjd
my program should provide following result: 3 because i have 3 characters which are similar in all the strings of the array(f,b,d).
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Mar 17, 2014
I am trying to find a concise way to write the sort methods for my class. I am supposed to make a program that can sort objects by a number of fields: year, rank, artist and title.
I used an idea from this thread : java - Sorting a collection of objects - Stack Overflow
And I am trying to use the custom comparator for my sort methods. However for some reason, the sortingBy variable fails to recognize any of the enum types.
Whenever I try to set the sortingBy variable equal to one of them, for example:
Java Code:
private Order sortingBy = Year; mh_sh_highlight_all('java');
I get a "Year cannot be resolved to a variable" error.
What I want to be able to do is make it so every time a specific method is called, say, for example sortTitle(), sortingBy will change to Title, then the SongComparator will sort using the case Title.
Is it possible to do this? I can't figure out how to modify SongComparator's object variables that way.
Java Code:
import java.util.Comparator;
public class SongComparator implements Comparator<Song> {
public enum Order {Year, Rank, Artist, Title}
public Order sortingBy;
[Code] .....
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Mar 30, 2014
I have a PriorityQueue called incoming, containing objects of type Vehicle.
All vehicles have a fuel level, that can be accessed by the getter method getFuelLevel().
I want to be able to choose to sort the queue so that the Vehicles with the lowest fuel levels are at the front of the queue.
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Oct 14, 2014
I have a requirement to find the greatest/maximum of the given list of Calendar objects in Java.
i.e., 2013/01/26
2014/03/03
2012/02/27
2014/01/15
So the above list of calendar objects are in Arraylist. I need to get the max/greatest among these. Eventually, the answer should be 2014/03/03
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Mar 18, 2014
I have to create a method with the following header :
public static <E extends Comparable<E> > void sort ( ArrayList<E> list , int left, int right)
i also had to create a swap cells method and position of max integer method. and also had to read the preserved data file in with a scanner. I implemented the comparable interface I am having difficulty sorting my list by the area. It has to be in descending order.
Geometric Object class: since it has comparator also am interested if i need to change this?
CODE:
Driver:
public static void main(String[] args) throws IOException, ClassNotFoundException {
Circle c1 = new Circle (4, "red", false);
Circle c2 = new Circle (2, "blue", true);
Circle c3 = new Circle (10, "blue", true);
Rectangle r1 = new Rectangle (10, 6, "yellow", true);
Rectangle r2 = new Rectangle ( 5, 11, "green", true);
ArrayList <GeometricObject> list = new ArrayList();
[Code] ....
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Jan 28, 2015
I want to clarify it whether this below code, when running this loop, will it create separate string objects as strings are immutable or else, will it keep the same reference(as each time inside loop, we use the same name 'rslt') and assign new string value for this?
while(inc < numberOfColumns){
String rslt=rs.getString(inc+1);
rowArr[inc] = rslt;
inc++;
}
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Jan 28, 2015
This piece of code i cannot change
public class Lab
{
public static void main(string args[]) {
int ar[]={7,5,2,8,4,9,6};
int sorted[]=new int[ar.length];
/// my code is right here this i can change i keep getting array required int found i'm not sure what i'm doing wrong i do know i need 2 for loops and an if statement.
[code]for(i=0;i<ar.length;i++){
for(j=i+1;j<ar.length;j++){
if(ar.length[i]>ar.length[j]
this piece of code cannot change
for(int i = 0; i<sorted.length; i++)
{
system.out.println("sorted[" + i + "] = " + sorted[i]);[/code]
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Sep 16, 2014
I need to sort a 2D array to look like this : [URL] ....
Here is the code that I have.
File 1:
import java.text.DecimalFormat;
public class Assignment1 {
public static void main(String[] args) {
String[][] rainArray
= {
{"January", "3.03"},
[Code] ....
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Nov 18, 2014
The following code is supposed to generate random integers and sort array1 and array2 using two different sorting methods. array1 is to be sorted with a "selection sort" method and array2 is to be sorted with the built-in Arrays.sort() method. However, array1 is the one that has a problem. It does not appear to output any values at all for array size of 4000 or more, such as array1[10000]. The assignment is to generate random integers, sort and benchmark the speeds at which array1 and array2 can generate and sort ints at array1[1000] array2[1000] array1[10000] array2[10000] array1[100000] array2[100000]
/**
*
* The following is a sorting and benchmarking program to sort
* array1 and array2 with 1,000 , 10,000 and 100,000 array sizes.
* array1 uses selection sort from section 7.4 of the book
* and array2 uses the built in Arrays.sort() method.
[code]....
I cannot post the output because the amount of data seems to have crashed the two previous posts I made on this topic due to the size of the problem.
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May 8, 2014
I'm in the process of doing a module grade book project and I have a working program, however I have to sort the array of students created first of all by name and then if they are identical, by student ID. I've looked at the compareTo method on several websites and I still don't know how to implement it in my code.
My main is as follows;
public class CommandLineTest {
public static void main(String[] args){
String moduleTitle=Input.getString("Enter module title: ");
double cwPercentage=Input.getDouble("Enter coursework percentage: ");
double examPercentage=Input.getDouble("Enter exam percentage: ");
[Code] .....
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Feb 3, 2015
I am trying to sort an array that I have by alphabetical order but I am having problems. Firstly the code that I have used to sort the array may not even do what I need but havn't got far enough to test it yet so go easy on me . I have read in some places when searching how to do this that I would have to create my own bubble sort in order to achieve this but I was hoping that Java had a built in sort method/function. Secondly I lack the knowledge in java to be able to assign an existing array or even a variable to the newly sorted array as I need the unsorted version with the original name and the newly sorted version as another.
code (This is not all of the code, I decided to include only what I thought was relevant):
import java.util.Arrays;
public class Sentence {
private String words[];
public Sentence(String[] words) { this.words = words; }
@Override
public String toString() {
return "Sentence{" +
"words=" + Arrays.toString(words) +
[Code] ....
Is it possible to shorten the sort function to just this?
public String sorted() {
return Arrays.sort(words);
}
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May 24, 2014
If I have a boolean array that contains 30 elements (boolean[] fish), how do I go about isolating every 10 elements to use for something specific?
Say there are 30 types of fish stored within the boolean array and 0-9 are fish found specifically in the Indian Ocean, 10-19 are fish found specifically in the Atlantic, and 20-29 are fish specifically found in the Pacific Ocean. And for those 10 fish [0-9], [10-19], [20-29], each is a different color (red, orange, green, blue, white, black, silver, yellow, purple and gold), where the colors and locations of the fish are enum types Colors and Locations.
How do I go about appointing those characteristics to the fish?
Ex: elements [0-9] are fish from the Indian Ocean and [0] is red, [1] is orange, [2] is green, [3] is blue, [4] is white, [5] is black, [6] is silver, [7] is yellow, [8] is purple, and [9] is gold.
elements [10-19] are fish from the Atlantic Ocean and [10] is red, [11] is orange, [12] is green, [13] is blue, [14] is white, [15] is black, [16] is silver, [17] is yellow, [18] is purple, and [19] is gold.
elements [20-29] are fish from the Indian Ocean and [20] is red, [21] is orange, [22] is green, [23] is blue, [24] is white, [25] is black, [26] is silver, [27] is yellow, [28] is purple, and [29] is gold.
Will I need to appoint those characteristics in the constructor after initializing fish = new boolean[30]?
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Dec 8, 2014
What the fastest way to sort an array of random integers. My instructor told me to look into an algorithm that uses 2n, but that is all he gave me. I am unable to find anything of the sort (pun intended there) on google, in my text, in my other java books or on here. The only thing that I have come up with are things like mergesort with the exception that the indicies of the Array have to be even. The program that I'm writing takes user input for a minimum to maximum range, the amount of numbers to fill the array in that range, and verbose.
I've tried bubbleSort but it takes forever to sort under the conditions below. I have seen a sorting algorithm that uses n (log n) but didn't really understand how that one worked.
Using the 2n algorithm, I should be able to test the range from 1 - 1000 and have it populate an array of of 1,000,000 random integers. It should be able to complete in a matter of miliseconds.
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Apr 10, 2014
I am sorting an array in ascending and descending order. I am using the nethods in Arrays as below
Arrays.sort(myArray)
I want to print both input and output array in sysout.
Object[] ipArray = [45,8,32,41,11,7];
Object[] opArray;
Object mArray = ipArray;
Arrays.sort(mArray); This is changing the ipArray too ?
How can I get my input array unmodified ?
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Apr 19, 2015
I'm working on an assignment that asks for the user to input 2 lists of numbers and my program will merge and sort the lists using arrays and 2 methods. I think I have most of it down, but I'm not sure how to go about getting the user inputs. In my current code, it's giving me a bunch of 0s instead of a sorted list.
import java.util.Scanner;
public class merge2sortedlists {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
[code]....
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Oct 21, 2014
I couldn't where the problem with this code. The question is : (Write a program that reads in nine integers and sorts the value in the ascending order. Next, the program restores the sorted integers in a 3 x 3 two-dimensional array and display the integers as shown in the result.) And this how i did it:
package test1;
import java.io.*;
import java.util.*;
public class test1{
public static void main(String[] args){
int[] hold = new int [9];
Scanner sc = new Scanner(System.in);
System.out.print("Enter 9 integers, press <Enter> after each");
{
for (int i = 0; i < hold.length; i++);
[Code] ....
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May 18, 2015
I need my code to print out the top three most common IP Addresses in the ArrayList. Right now I have it printing out the top IP Address. I am a little confused as to how to get it to print out three. Every time I change something, It doesn't give me the correct results
My Code:
public class Log_File_Analysis {
private static ArrayList<String> ipAddress = new ArrayList<>();
private static String temp , mostCommon;
static int max = 0;
static int num = 0;
[Code] .....
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Apr 21, 2014
I'm trying to calculate the average of grades that a user puts in. Here is my code so far:
public static void main(String[] args) {
Scanner input = new Scanner (System.in);
System.out.println("Please enter an array of grades seperated bt a comma.");
input.nextLine();
String arrayOfGrades = "100,50,100";
String[] grades = arrayOfGrades.split(",");
[Code] .....
I think I'm on the right track, the only big error I'm really getting is the line: sum += grades[i]. It's saying string can not be converted into a double.
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Nov 20, 2014
This time I am having difficulties with selection sort method, but not with the method itself (I think). So I need to sort an array and return the result of each step.
This is the main code:
public class Functionality {
public static int[][] selctionsort(int[] a) {
for (int i=0; i<a.length; i++) {
int least = i;
for (int j=i+1; j<a.length; j++)
[Code] ....
And this is the Test folder:
import static org.junit.Assert.assertArrayEquals;
public class PublicTests {
public static void main(String[] args) {
int[] a = new int[] { 35, 7, 63, 42, 24, 21 };
int[][] b = new int[][] { new int[] { 7, 35, 63, 42, 24, 21 },
[Code] ....
Now I am not sure what should I write in return since the 2nd (test) project has int[][] and in my main project I am working with int [].
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Jan 29, 2015
public class lab
{
public static void main(String args[] )
{
[Code]....
//The program does run but when i run it prints out the new array with a 2 at index 0 and zeros for index 1-6. my objective is to have the new array print out the ar{7,5,2,8,4,9,6} array in order. There is some code I cannot change I have pointed out which one I can't change.
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Apr 10, 2015
Every time i try and add a new word to personalDictionary, it only replaces the first index. In my personalAdd method i had tried to add a running count to advance the position it would be saving in but it doesn't seem to be working correctly...
Java Code:
import java.util.Arrays;
import java.util.Scanner;
import java.io.File;
import java.io.PrintWriter;
import java.io.FileNotFoundException;
public class SpellingChecker
[Code] ....
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