Displaying Random Value Of Integers And Then Finding Missing Integer From Values In Array
Feb 7, 2015
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
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");
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++);
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'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;
-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 am working on this project that wants me to write a program that inputs 20 numbers, each of which is between 10 and 100, inclusive. As each number is read, display it only if it is not a duplicate of a number already read. The only part I am confused about is how to go about checking for duplicate values that the user may enter. And IF the user does input a duplicate value, it should not be stored again.In addition, the value entered should be printed out after it is entered along side the value that have been previously entered by the user such as:
23 23 45 23 45 67 23 45 67 12 and so on.
I am still fairly new at java programming.
import java.util.*; public class NumberArray { public static void main(String[] args) { // declare an array with 5 elements
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++)
filling out a Random array: An Array of Specific Length Filled with Random Numbers This time what I need to do is take the elements from this Random array and assign them to a new Byte array:
for(int i = 0; i < limit-10; i++) { Random dice = new Random(); int randomIndex = dice.nextInt(array.length); if (array[randomIndex] < 128) { System.out.print(array[randomIndex] + " "); } else if (array[randomIndex] >= 128) { System.out.print(array[i] + " "); } } byte[] noteValues = new byte[]
{ 64, 69, 72, 71, 64, 71, 74, 72, 76, 68, 76 }; //This is the byte array filled manually!
I've tried amending the manual input to fit in with the Random array, as follows:
byte[] noteValues = new byte[] { array[randomIndex] };
In this case, however, the Byte array can't interpret the int values. Also, if the Byte array is outside the 'for' loop, array[randomIndex] cannot be resolved.
I am having a hard time trying to figure out how to print random numbers from a an array list. I tried google but nothing worked. I have to pick certain values from two lists and print them on the screen. I have included comments in the code to facilitate the explanation.
import java.util.Random; public class Parachute { public static void main(String[] args) { Random randomNumbers=new Random(); int number; int array []={1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21}; char A[] = {'a', 'b', 'c','d','e','f','g','h', 'i','j','k','l','m','n','o','p','q'};
Write a program that creates an array that can hold 9 double values that represent baseball batting averages for a starting baseball lineup. Use a for loop to populate array with random double values in the range of 0.00 to 0.500. Recall that "double" values are what Java calls "real" numbers. Use a second for loop to print the values in the array with one number per line. Finally, use a third for loop to traverse the array and find and print the maximum batting average in the array. Note: you will need to use String.format to control the precision of a double number when you print it- Here is my code so far:
public class P2F { public static void main (String[] args) { double [] player= new double [9]; //player[0]= Math.random(); for (int index=0; index < player.length; index++) {
[Code] ....
When I open the terminal window I get different variations of this [D@4545c5]. I would like to know all the things I am doing wrong.
I have been assigned to write a program that has a user input random numbers then the program is to sort them in different ways. I have the coding for the different sorts but, I have an error saying that I am missing a return statement in the "Bubble" method. I am trying to return "arr[i]" in the "for loop" which gives me this error, and when I try to take the "return arr[i]" outside of the "for()" loop the error reads the it cannot locate variable "i".
import java.awt.* ; import java.awt.event.*; import javax.swing.*; public class SwingSorts extends JFrame implements ActionListener { JRadioButton bubble; JRadioButton selection;
So I wrote a method that simply calculates the sum of all integers between 1 and a given integer n. The method works fine however, as n gets big the solution will have time and space problems. Some I'm just curious if there is a better method than my iterative one that would produce a better Big O value.
public static int sum(int n) { int total = 0; for (int i = 1; i <=n; i++) total += i; return total; }
I have a super class and an inherited class. What it is supposed to do is display random images in one applet. The images dont match the words and images dont match the wording. What am I doing wrong? Probably a few errors.
Super Class:
import java.awt.Color;; public class Dukes { private Color noseColor = Color.red; // default Dukes have red noses private String action = "../../images/duke/dukeWave.gif"; //default Dukes are friendly private String whatDoing = "Give me something to do"; private String message= ""; public Dukes() { int rint = (int)(Math.random() * 3); // randomly generates a 0, 1, or 2 if (rint == 0)
How do I code this without having the need to use iterator? Code a Java method that accepts an ArrayList of integers and an integer. The method should delete all elements in the array list exactly divisible by the integer and return the number of remaining elements.
I am obviously new to programming and Java so I set myself the goal of creating a very simple auto type style of program so it gets the users input and relays it out again but potentially to another window (I am currently testing to notepad). The reason I am trying to make it is because i thought it could be quite simple and I can build on it as a project to make it better.
The issue I am having is that it outputs the first character to the window I am selected (again testing into notepad) but then stops and doesn't output anything else. I tried to figure out what was going on by putting a System.out.println(arr[6]); after the delay method but it just output a line so almost like what I was putting into the array was only storing the first character of the string? I cannot figure out why that would be...
import java.awt.*; import java.awt.event.InputEvent; import java.awt.event.KeyEvent; import java.util.Scanner; public class MyBot public static void main(String[] args) throws AWTException { //initialising robot Robot r = new Robot(); Scanner input = new Scanner(System.in);
Write a method maxOccurrences that accepts a list of integers as a parameter and returns the number of times the most frequently occurring integer (the “mode”) occurs in the list. Solve this problem using a map as auxiliary storage.
I am using primeface in this project. I have a database with orders, order details and customers. The index page displays the order details and I click on one of the orders I want the customer details of that order to be displayed. But right now when I click on an order the dialog box that appears is empty. I'm not sure if the problem is with the jsf for the customer class.
So I'm learning java from a website and I was tasked with creating a simple program which allows the user to enter a series of integers, then finally when they decide to input a non-integer the program will print the maximum and minimum values of the integers they entered. So for example if they entered 5, 4, 3 and 2 then enter a non-integer the program would output 5 (maximum value), then 2 on a new line (minimum value).
Here is my code:
import java.util.Scanner; public class MaxMinPrinter { public static void main(String[] args) { Scanner in = new Scanner(System.in); int max = Integer.MIN_VALUE; int min = Integer.MAX_VALUE;
[Code] ....
And this is what the output looks like:
Actual output ------------------------------------------- Enter an integer: 5 - 10 - - Enter an integer: -4 - 8 - -6 - - Enter an integer: 11 - -1 - - Enter an integer: q - -1 - -6
When it's supposed to look like this:
Expected output ------------------------------------------- Enter an integer: 5 Enter an integer: 10 Enter an integer: -4 Enter an integer: 8 Enter an integer: -6 Enter an integer: 11 Enter an integer: -1 Enter an integer: q 11 -6
Write a subclass of BasicGame in which the computer asks the user to choose a whole number from 1 to 100, inclusive. The program then makes a number of guesses. After each guess, the user tells whether the guess is too high, too low, or exactly right. Once the computer "knows" what the correct number is, the computer tells the user the correct number and the number of guesses tried. Have the program ask the user after each game whether she wants to play again. Design the program so that it always guesses the correct answer by the seventh try at latest. Hint: Have two instance variables that keep track of the smallest and largest values that the guess could be (initially 1 and 100). After each wrong guess, update these smallest and largest values appropriately.This is what I have written for the assignment:
Java Code:
import javax.swing.JOptionPane; public class GuessThatNumber extends BasicGame { private java.util.Random randy; private int itsCompNumber; private int itsHigh = 99; private int itsLow = 1;
[code]...
The part I'm having trouble with is changing the high and low values based on the input of "too high" or "too low," which I tried in the continueGame method... When I test the game, the values for itsCompNumber aren't restricted by the user's input at all, and I'm not sure how to fix it.
For part of my program, I am trying to ask the user for input on generating a number of random characters. I have already done this with integers and doubles, how would I do this for characters using ASCII values? Would I use the same format as I did for generating integers (Shown in code)?
import java.util.Random; import java.util.Scanner; public class NewNumberCharacter { public static void main(String[] args) { // Create a Scanner Scanner input = new Scanner(System.in);
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];
I have assigned random numbers to an 2D array, and I had to write a method that prompts the user for a number between 100 and 200. If that number is in the array, it should return 1. If not, 0. It only stays 0 though, even when the number matches one of the numbers in the array.
public static int Findit(int[][] numbers, int guess) { int Findit = numbers[0][0]; int i = 0; int x = 0; boolean found = false; for(i=0;i<numbers.length;i++)
