This code is designed to interpret an array of integers and rearrange it so that the even numbers come before the odd. But it fails when I run it against my test?
public void evensLeft(int[] array) {
int myFun[] = new int[array.length];
int k = 0;
for (int i = 0; array.length-1 > i; i ++) {
if (array[i]%2==0) {
myFun[k] = array[i];
k++;
[Code] ....
I'm making a method to take an array of integers and rearrange the numbers from least to greatest, using for loops.
I'm getting the error "java. lang. ArrayIndexOutOfBoundsException: 8,
Portion of the ArrayMethods class with the sorting method
Java Code:
public static Integer[] sortArray (Integer[] a)
{
int swap;
for (int i = 0; i < a.length; i++)
[code]....
So I need to generate 10 random integers in the range 1-20 but i have to store them in an array called numbers. Then I have to call a method called displayArray which displays the contents of the array and for the assignment i have to use a for loop to traverse the array. The method header for the displayArray method is:
public static void displayArray(int[] array)
This is what I have done
public class RandomIntegers {
static int numbers = 0;
public static void displayArray(int[] array) {
System.out.println(numbers + "Numbers Generated");
[Code] .....
I have double checked this code over and over and I just can't find the problem.
What I'm trying to do is take a file and input it into an 2D array.
Ultimately, I should convert the array of integers to an array of characters, then print it out. The file contains a set of ASCII values.
After printing it out, I should then create methods to manipulate the image produced.
Using 2D arrays is a requirement for this exercise.
I think that somehow I'm overcomplicating this and the solution is a lot more simple than I think, but I can't think of what to change.
The error I am getting is:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 40
at main.main(main.java:17)
Java Code:
import java.util.*;
import java.io.*;
public class main {
public static void main(String[] args)
throws FileNotFoundException {
String[][] data = new String[22][40];
[Code] .....
how to read and understand the API's. I've got an array list and I was wondering if there was a method that can randomly re arrange the elements in terms of their index positions.
View Replies View RelatedI am wondering how one rearranges an existing complex UI using scene builder. I have tried, for example, to add a scrollpane around another pane that was already nested deep in my layout and did not find a way to do this. Is this not supported or am I just not getting how it's done? Typical practical examples of this would be that one introduces a split pane around an existing part of the layout and moves existing controls/panes including all their configuration (resource keys, bindings etc.) into one part of the split pane to add more functionality into another.
View Replies View Relatedimport java.util.Arrays;
import javax.swing.JOptionPane;
public class Student {
public static void main(String args[]) {
String [] A =new String [4]; //krijon tabelen e emrave
[Code] ....
It Prints [firstname,secondname,thirdname,fourthname]
and [0,0,7,9]
The problem is that the first 2 integers of the second array are always 0 even if i put another grade like for example 6 or 7...
Our teacher asked to input the names and grades of the students using JOptionPane and then find the MINIMUM grade and how many times this grade is repeated...
I am trying to write a method that returns the busiest hour in a logAnalyzer class that read web server data and analyze hourly access patterns and stores them in an array. My problem is, in order to get the busiest hour, I need to go through the hourCounts array to find the element with the biggest count.
View Replies View RelatedI have a method that receives an array of integers and saves the ID of the user inside the array of integers and I keep getting the error: "int[] cannot be converted to int".Here is the code:
public boolean Borrow (String TitleOrAuthor,int id){
int count = 0;
int b1 = 0;
int BookCount [] = new int [b1];
for (int i=0;i<Bcount;i++){
if(Booklist[i].getTitle().equals(TitleOrAuthor))
for(int j=0;j<b1;j++){
BookCount [j]= Booklist[i].getCopies();
BookCount [j]= id;
b1++;
[code]...
I am workinh with a couple of functions that deal with two dimensional (square) arrays of integers, doing things like checking equality, etc. For example, I know that I get an ArrayOutOfBoundsException in the isEqual function, but I don't know why.
public class MatrixUtils {
//This function checks if two matrices are equal
public static boolean isEqual(int A[][], int B[][]) {
for(int i=0; i<A.length; i++) {
for(int j=0; j<A.length; i++) {
if (A[i][j] != B[i][j]) return false;
[Code] ....
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.
I am trying to create a method that takes an array of integers and prints it out using System.out.print. I'm having trouble creating the right way to print it out since I cannot find a way to convert the int array to a string to print it out.
public static String printArray(int[] num){
for (int i=0; i<num.length;i++){
String msg = num[i];
}
return System.out.print(msg + " ");
}
I am pretty new to Java and am just learning about two dimensional arrays. I think that I understand the concept, but I seem to be having trouble adding stuff to my array. I wanted to make an array to hold both strings and integers, but wasn't sure if I could put integers in a string array. So I thought that I would be able to convert my integers to string and then add them. This however causes an error. This is my code(yes its probably not the best):
static String [][] students = new String [14][4];
static int number = 0;
String fName, lName, fullName;
int test1, test2, test3, test4;
String a, b, c, d;
[Code] .....
I have a problem where i have to write some code to read through an int array and print out the different integers and how many times they occur. For example:
if the array contained the numbers 1,4,2,3,5,4,4,7,5,4,3,6,8,6,4,
i would need the print to appear something like this
integer: 1, times: 1
integer: 4, times: 5
integer: 2, times: 1
etc
as the array is read sequentialy from element 0 to the end. the program should find the integer value in the first element (increment a counter by 1) and then search all other elements to see if the integer reoccurs (counter++ for each time it reappears). obviously the counter would be the 'times' value in the second column.
My problem is i can get this accomplished yet i cant get the program to recognise when it has already registered an integer in a previous element and skip to the next element looking for a new integer. SO for each element in the array it prints the integer and then searches the entire array for the integer again and increments the counter accordingly. so in essence there is a line printed for each integer the number of times it actually occurs.
I simply wish to have my code to find an integer and the number of times it occurs. and then disregard the elements it has registered the previous integer in.
Also, keep in mind that i am NOT permitted to use any new data structures/arrays for storing/remembering values. I can only use int and double variables throughout.
what i have so far is this: with the array being customerID[] :
Java Code:
int num;
int counter;
for(int count = 0; count < customerID.length; count++)
{
counter = 0;
num = customerID[count];
for(int count2 = 0; count2 < customerID.length; count2++)
[Code]...
The output for the int array 1,1,3,0,3,2,0,4,1,3, looks something like this:
Integer: 1, Times: 3
Integer: 1, Times: 3
Integer: 3, Times: 3
Integer: 0, Times: 2
Integer: 3, Times: 3
Integer: 2, Times: 1
[Code]...
and as you can see lines are repeated for each time the same integer occurs in a new element. i just need my code to skip an element if the integer has been previously encounterd and recorded. i.e i need it to look more like this :
Integer: 1, Times: 3
Integer: 3, Times: 3
Integer: 0, Times: 2
Integer: 2, Times: 1
Integer: 4, Times: 1
with the first encountered integer being checked throughout the array and then moving to the next integer/element which is not the same as any previous.
I'm required to create a program that finds the minimum value in an Array of integers.
Here is my approach :
public class Person {
public static void main(String [ ] args){
int theArray[]=new int [10];
int result = 0;
for (int i:theArray){
if (i < Integer.MAX_VALUE)
[Code]...
I can't really progress from this position. I keep getting told to change the return type to int on main method, then when i do it says change it to void..
I wrote this simple piece of code to find the number in the given array of Integers. The program works fine although it shows a couple of errors when i modify it a little bit.
public class DemoLabel{
public static void main(String [] args){
int[][] arrofInts={
{32,45,67,87},
{23,44,55,66},
{12,47,87,56},
{23,44,12,78}
[Code] .....
In the disp() method,Suppose i only want to pass two arguments i.e disp(i,j) given that searchFor variable is visible in the entire class but when i use disp(i,j) i get the following error
DemoLabel.java:38: error: cannot find symbol System.out.println("The number "+searchFor+" is at the location"+i+" , "+j);
^
symbol: variable searchFor
location: class DemoLabel
So i decided to declare the
int searchFor
as
public int searchFor
But the compiler threw another error saying that it was a Illegal start of expression
Also,when i add a SOP line after the label search: it shows the error
DemoLabel.java:25: error: undefined label: search
continue search;
^
Although i got the program to work it would be useful if i could understand why it doesn't work with the modifications.
The main Method
-Create a main method declares and creates an integer array called nums that can hold 15 integers.
-Use a for loop to fill that array with multiples of 3: 0, 3, 6, 9, etc.
-Then use similar for loop to print each value in the array on one line, with each value separated by a single space.
-Compile and run the program to see the result:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
As you write other methods, you'll also modify the main method to make calls to them. The printArray MethodWrite a method called printArray that accepts an integer array as a parameter. This method does not return a value, and must be declared as static so that the main method can call it. Instead of printing the array in the main method, move that loop into this method. Call the printArray method from the main method. Compile and run the program to verify it prints the sam result as before.Add a println statement so that after printing the array values on one line, it then moves to the following line.Finally, modify the loop in the printArray method so that, instead of using a traditional for loop, it instead uses a for-each loop. Compile and run the program again.
Part III: More Array Methods
The linearSearch Method In lecture we looked at a method that performed a binary search on a sorted array. A much simpler (though much less efficient) search is a linear search, that simply starts at the front of the array and looks at each element in turn until it finds it or reaches the end.Create a method called linearSearch that accepts an integer array and a single int value as parameters. The goal of the method is to find the second parameter (the target) in the array. The method should return a single int representing the index of the target value. This method should not print any output itself. In this method, use a traditional for loop to scan through the elements in the array. As soon as you find the target value, return the index of that value.
If you scan through the entire array without finding the target value, return a -1.Modify the main method to call the linearSearch method and print the results. Call it twice, searching for the value 18 (which it should find) and the value 10 (which it should not). Including the previous activity, the output of the main method should now look similar to this:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sumArray Method
The sumArray method should take an integer array as a parameter and return a single integer representing the sum of all values in that array.Use a for-each loop to access each value in the array and compute a running sum. After the loop, return the total.Call the method from the main method, producing the following augmented output:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sum of this array is 315
The addValue Method...The addValue method should accept an integer array and a single int as parameters. The purpose of the method is to add the second parameter to EACH value in the array. The addValue method does not return a value, but the elements inside the array will be modified. Call the addValue method from the main method, adding 100 to each element in the array. Then call the printArray method again to see the modified array values:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sum of this array is 315 100 103 106 109 112 115 118 121 124 127 130 133 136 139 142
Test a Different Array..Finally, duplicate the content of the main method to perform similar tests on another array. Instead of filling it with multiples of 3, fill it with multiples of 4. And instead of using an array size of 15, use an array size of 20.Modify the values search for to include one that is in the array and one that isn't.Rerun the main method and carefully check the results.If you haven't been doing it all along (which you should), make sure the appropriate class and method documentation is included.When you're satisfied that all methods are working correctly, modify the main method to delete the second array tests.
I'm trying to generate random 100 numbers, from 0 to 9, in an array using Math.random, but it only outputs 0s which is very confusing to me. Also, I need to be able to count how many different integers there are like 0s, 1s, 2s... 8s, 9s.
Here's my code, I only got as far as the array then got stumped on the counting part.
import java.util.Arrays;
public class countDigits {
public static void main(String[] args) {
//Create random generator and values
int numbers = (int)(Math.random() * 10);
int arrayCount = 1;
[Code] ....
and my results
0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
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] ....
Write a function that accepts an array of non-negative integers and returns the second largest integer in the array.
Return -1 if there is no second largest.
The signature of the function is int f(int[ ] a)
Examples:
if the input array isreturn{1, 2, 3, 4}3{{4, 1, 2, 3}}3{1, 1, 2, 2}1{1, 1}-1{1}-1{}-1
In the signature what I understood is, I should write my function with the given signature,
The return type is "int"
method name is "f"
parameter is "a" right ?
Writing my doubts beside the particular line in the code
public static void main() // In the answer why they didn't use the class ?
In main method why they didn't use parameters ?(String[] args)
{
a1(new int[]{1, 2, 3, 4}); // what is "a1" here is it array name ? this line initializing the array ?
a1(new int[]{4, 1, 2, 3});
a1(new int[]{1, 1, 2, 2});
a1(new int[]{1, 1});
a1(new int[]{1});
a1(new int[]{});
}
static int a1(int[] a) // what is "a" here parameter ? and "a1" is method name ? why they used the array name and method name same ?
{
int max1 = -1;
int max2 = -1;
for (int i=0; i<a.length; i++)
[Code] .....
I have a problem where I have to create random integers from 1 to n + 1. When the array is displayed I have to find the missing integer from the values that are displayed and show that value. I have to use O(n^2) and O(n) operations. I have created this code so far but I cannot figure out how to make my values display n + 1. It is only displaying values 1, 2, 3, 4 and 5 in random order. I also cannot figure out how to find the missing value. I have created a boolean displayed statement but can't determine how to use it in this code.
=Java
import java.util.Random;
public class Task6
{
public static void main(String[] args)
{
int[] numbers = new int[7]; //create array of numbers
Random random = new Random();
boolean displayed = false; //boolean value to determine if number was displayed
[code]....
I have to make two classes. The first one crates an instance of an array of several integers and prints data (average, greatest, lowest, et cetera) based on the second class, which contains the methods. I'm having a problem with the syntax for the first class required to use the methods.
Here's a shortened version of what I have right now just based on processing the number of integers in the array (because if I can get just one method properly connected, I could figure out everything else).
Driver
import java.util.Arrays;
public class ArrayMethodsDriver
{
//Creates the ArrayMethods object
public static void main(String[] args)
{
int[] a = {7,8,8,3,4,9,8,7};
[Code] ....
When I try to compile this, I currently get the "class expected" error on the count part.
After the code is executed the array is supposed to contain 2,3,5,3,2. However, prime[4-0]= prime[i] and prime[4-1]= prime[i]... doesn't the loop terminate before it iterates a third time? Why are there five integers instead of only two?
int[] primes= {2,3,5,7,11};
for (int i=0; i<2; i++)
{
primes[4-i]= primes[i];
}
Create a loop where you add the integers from 1 to 50.
public class Sum50 {
public static void main(String[] args) {
int sum = 0;
int max = 50;
for(int i = 0;i <= max; i++){
sum=sum+i;
}
System.out.println("Sum is " + sum);
}
}
I was trying to get sum of numbers between two given integer and managed to do it.
public int sum(int a, int b) {
int sum=0;
while(a <= b) {
sum+=a;
a++;
}
return sum;
}
in here; when I enter the values i.e 2 and 5, it calculates 2+3+4+5 and gives me the result 14.
my question is, how could I exclude a and b in this calculation ( in this case exclude 2 and 5 and return 3+4 )
Bonus question ; how could I only calculate the odd (or even) numbers between those integers?
I need to write a class in that uses the For loop and does the following things: asks user to input two integers, the second larger than the first. Next, use a for loop to sum the numbers between the two integers, including the original integer. For example: 5&8 would be 5+6+7+8 and lastly prints out the sum of this.
I have successfully been able to do the first part but when it comes to the For Loop I am a bit lost here is what I have so far
import java.util.Scanner;
public class Question3 {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Please enter an integer");
int num1 =sc.nextInt();
System.out.println("please enter a larger integer");
int num2=sc.nextInt();
int sum=0;
for(int i=num1; i<=num2;i++);
}
}