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Parameters, methods and inputs

I am a beginner in Java and I am wondering if there is a way to use one input from the user in more than one method? I am making a program that is supposed to take some inputs (integers) from the user and control the inputs, then calculate the average and lastly count the occurrence of the inputs?
I have one main method + 3 different methods (one calculates the average etc). I have tried a lot of different things, but haven't seemed to understand the point with parameters and how they work.
So this is just a quick overview.
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("How many elements do you want to enter");
int value = sc.nextInt(); //Number of how many elements the user want to enter
int[] input = new int[value]; //An array with all the values
}
public int secureInt(int number, int[] input, int value) {
if (!Integer.parseInt(number)) {
System.out.println("Invalid input");
} else {
for (int i = 0; i < value; i++) { //Add all the inputs in the array
input[i] = sc.nextInt();
}
}
public double averageCalculator (int value, int[] in){
double average; // The average
double sum = 0; // The total sum of the inputs
if (int i = a; i < value; i++) {
sum = sum + in[i];
}
average = sum / value;
return average;
}
//Count the occurence of inputs that only occure once
public static int countOccurence(//what parameter should i have here?) {
int count = 0;
}
}

Here is some code that may be helpful to you. The idea is to try to emulate or imitate the style & best practices in this excerpt:
import java.util.Scanner;
public class ArrayFiller {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("How many elements do you want to enter");
int input_element_count = sc.nextInt(); //Number of how many elements the user want to enter
int element_count = input_element_count;
int[] array = new int[element_count]; //An array with all the values
enter_elements_of_array(array, element_count, sc);
double average = averageCalculator(array, element_count);
printArray(array);
System.out.println("The average of the entered numbers is " + average);
}
public static void printArray(int[] array) {
System.out.print("The array you entered is : [");
for (int element : array) {
System.out.print(" " + element + " ");
}
System.out.print("]" + "\n");
}
public static void enter_elements_of_array( int[] array, int element_count, Scanner sc) {
for (int i = 0; i < element_count; i++) { //Add all the inputs in the array
System.out.println("Please enter element " + (i+1) + " of " + element_count + ":");
array[i] = sc.nextInt();
}
}
public static double averageCalculator ( int[] array, int element_count){
double average; // The average
double sum = 0; // The total sum of the inputs
for (int i = 0; i < element_count; i++) {
sum = sum + array[i];
}
average = sum / element_count;
return average;
}
//Count the occurence of inputs that only occur once
public static int countOccurence(int[] array) {
int count = 0;
// algorithm for counting elements with cardinality of 1
return count;
}
}

Java Method(DiceProblem) [closed]

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Well, the program that follows, when run, will let me ‘roll a pair of dice’ n-times (i.e.
generate a number between 1 and 6), where n is a positive integer entered. The
program then outputs the pair of numbers (‘rolled dice’), as well as the sum of the numbers
(each pair of dice). The pairs of numbers are stored in a 2-dimensional array, and the sum
of each pair are stored in a single-dimensional array.
import java.util.Scanner;
import java.util.Random;
public class diceProblem{
public static void main(String[] args){
Scanner input = new Scanner(System.in);
System.out.print("Enter the amount of times a pair of dice will roll: ");
int times = input.nextInt();
int[][]dicePairs = rollDicePairs(times);
System.out.println("The rolled pairs of numbers are: ");
printDicePairs(dicePairs);
int[][]dicePairsSums = addDicePairs(dicePairs);
System.out.println("The sum of each pairs of numbers are: ");
printDicePairsSums(dicePairsSums);
}
public static int[][]rollDicePairs(int times){
int[][]dice = new int[times][2];
Random die = new Random();
for(int x=0;x<times;x++){
for(int y=0;y<2;y++){
dice[x][y] = 1+die.nextInt(6);
}
}
return dice;
}
public static void printDicePairs(int[][]dicePairs){
for(int[]pair: dicePairs){
for(int roll: pair){
System.out.print(roll+" ");
}
System.out.println("");
}
}
public static int[][]addDicePairs(){
int[]pairSums = new int[dicePairs];
for(int x=0;x<pairSums.length;x++){
int sum = 0;
for(int y=0;y<dicePairs[x].length;y++){
sum += dicePairs[x][y];
}
pairSums[x] = sum;
}
return pairSums;
}
public static void printDicePairsSum(int[]dicePairsSums){
for(int sum: dicePairsSums){
System.out.print(sum+" ");
}
}
}
The problem is there are too many errors with this program and it doesn't run or output the pairs of number and the sum

You code does not compile. Below is the corrected code that does compile and it also produces the correct results when you run it. Compare it to your code so as to spot the differences.
import java.util.Random;
import java.util.Scanner;
public class DiceProb {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter the amount of times a pair of dice will roll: ");
int times = input.nextInt();
int[][] dicePairs = rollDicePairs(times);
System.out.println("The rolled pairs of numbers are: ");
printDicePairs(dicePairs);
int[] dicePairsSums = addDicePairs(dicePairs);
System.out.println("The sum of each pairs of numbers are: ");
printDicePairsSum(dicePairsSums);
}
public static int[][] rollDicePairs(int times) {
int[][] dice = new int[times][2];
Random die = new Random();
for (int x = 0; x < times; x++) {
for (int y = 0; y < 2; y++) {
dice[x][y] = 1 + die.nextInt(6);
}
}
return dice;
}
public static void printDicePairs(int[][] dicePairs) {
for (int[] pair : dicePairs) {
for (int roll : pair) {
System.out.print(roll + " ");
}
System.out.println("");
}
}
public static int[] addDicePairs(int[][] dicePairs) {
int[] pairSums = new int[dicePairs.length];
for (int x = 0; x < pairSums.length; x++) {
int sum = 0;
for (int y = 0; y < dicePairs[x].length; y++) {
sum += dicePairs[x][y];
}
pairSums[x] = sum;
}
return pairSums;
}
public static void printDicePairsSum(int[] dicePairsSums) {
for (int sum : dicePairsSums) {
System.out.print(sum + " ");
}
}
}

Bubble sort and input

I have to enter 3 jumpers who will jump 2 times.
Here is an illustration via my console for the first jump. (it's step is ok)
Then, for the second jump. I have to sort the first jump from the smallest to the biggest.
So, I have to retrieve the jumper Emilie and not Olivia.
I don't understand how to do this ?
I think my problem is my sortBublle() method ?
import java.util.*;
class Main {
public static void main(String[] args) {
String[] arrayJumper = new String[3];
int[] arrayJump = new int[3];
encoding_jump_1(arrayJumper, arrayJump);
sortBublle(arrayJump);
encoding_jump_2(arrayJumper, arrayJump);
}
public static void encoding_jump_1(String[] arrayJumper, int[] arrayJump){
Scanner input = new Scanner(System.in);
int iJumper = 0;
int iJump = 0;
System.out.println("Jump 1 : ");
for(int i=0; i<arrayJumper.length; i++){
System.out.print("Enter jumper " + (i+1) + " : ");
String jumper = input.next();
arrayJumper[iJumper++] = jumper;
System.out.print("Enter for the jumper " + arrayJumper[i] + " the first jump please : ");
int jump = input.nextInt();
while(jump <= 9 || jump >=111){
System.out.print("Error ! The jump should to be between 10 and 100 please : ");
jump = input.nextInt();
}
arrayJump[iJump++] = jump;
}
}
public static void sortBublle(int[] arrayJump){
int size = arrayJump.length;
int tempo = 0;
for(int i=0; i<size; i++){
for(int j=1; j < (size - i) ; j++){
if(arrayJump[j-1] > arrayJump[j]){
tempo = arrayJump[j-1];
arrayJump[j-1] = arrayJump[j];
arrayJump[j] = tempo;
}
}
}
}
public static void encoding_jump_2(String[] arrayJumper, int[] arrayJump){
Scanner input = new Scanner(System.in);
int iJump = 0;
System.out.println("Jump 2 : ");
for(int i=0; i<arrayJumper.length; i++){
System.out.print("Enter for the jumper " + arrayJumper[i] + " the second jump please : ");
int jump = input.nextInt();
while(jump <= 9 || jump >=111){
System.out.print("Error ! The jump should to be between 10 and 100 please : ");
jump = input.nextInt();
}
arrayJump[iJump++] = jump;
}
}
}
Thank you very much for your help.

You are only sorting arrayJump --> You need to sort both arrayJumper and arrayJump`
...
if(arrayJump[j-1] > arrayJump[j]){
tempo = arrayJump[j-1];
arrayJump[j-1] = arrayJump[j];
arrayJump[j] = tempo;
tempName = arrayJumper[j-1];
arrayJumper[j-1] = arrayJumper[j];
arrayJumper[j] = tempName;
}

Compare scanner input to array

Idea:
User inputs their bets by typing either 'W','L' or 'T' (wins, losses or tie). Program generates random results within these parameters. User input and result gets printed, and a score is presented based on correct bets, which is supplied by the program.
Im having issues on how to proceed with comparing user generated input from scanner to an arraylist that produces a random result.
If it were not for the multiple "questions" and "answers" I could use a (val.equals(input)) of sort. However, each individual bet is random and must be matched against the users bets to sum up the users score, that complicates it.
Any help appreciated.
public class test3 {
public static void main(String[] args) {
int score = 0;
System.out.println("Betting game initiating... \nType 'W' for win, 'L' for loss and 'T' for tie.");
Scanner input = new Scanner(System.in);
String array[] = new String[5];
for (int i = 0; i < 5; i++)
{
System.out.println("Please enter your bet:");
array[i]=input.nextLine();
}
List<String> list = new ArrayList<String>();
list.add("w");
list.add("l");
list.add("t");
System.out.println("This week wins, losses and ties loading...\n");
System.out.println("Result:");
test3 obj = new test3();
for(int i = 0; i < 5; i++){
System.out.print(obj.getRandomList(list) + " ");
}
System.out.println("\n\nYour bets were:");
for (int i = 0; i < 5; i++){
System.out.print(array[i] + " ");
}
System.out.println("\n\nYou were correct on: " + score + " bettings");
}
private Random random = new Random();
public String getRandomList(List<String> list) {
int index = random.nextInt(list.size());
return list.get(index);
}
}

One way to do this is in the code below.
You basically need to compare each element of your input with each element of the random list so run loop.
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Random;
import java.util.Scanner;
public class Test {
private Random random = new Random();
public static void main(String[] args) {
int score = 0;
System.out
.println("Betting game initiating... \nType 'W' for win, 'L' for loss and 'T' for tie.");
Scanner input = new Scanner(System.in);
String array[] = new String[5];
for (int i = 0; i < 5; i++) {
System.out.println("Please enter your bet:");
array[i] = input.nextLine();
}
System.out.println("\n\nYour bets were:");
for (int i = 0; i < 5; i++) {
System.out.print(array[i] + " ");
}
List<String> list = new ArrayList<String>();
list.add("w");
list.add("l");
list.add("t");
System.out.println("This week wins, losses and ties loading...\n");
System.out.println("Result:");
Test obj = new Test();
List<String> randList = new ArrayList<>();
for (int i = 0; i < 5; i++) {
randList.add(obj.getRandomList(list));
}
for(String randBet : randList){
System.out.print( randBet + " ");
}
System.out.println("");
int counter = 0;
for (String yourbet: Arrays.asList(array)){
if(randList.get(counter).equals(yourbet)){
score++;
}
counter++;
}
System.out.println("\n\nYou were correct on: " + score + " bettings");
}
public String getRandomList(List<String> list) {
int index = random.nextInt(list.size());
return list.get(index);
}
}

I removed test3 for simplicity, but basically you need save results on array and generate random results and saving them (i.e a list). Then you have to iterate through and compare each game result, and if your bet is correct, just add one to score. Check the code below:
Main:
public static void main(String[] args) {
int score = 0;
String array[] = new String[5];
List < String > randomResultList = new ArrayList<String> ( );
System.out.println("Betting game initiating... \nType 'W' for win, 'L' for loss and 'T' for tie.");
Scanner input = new Scanner(System.in);
for (int i = 0; i < 5; i++)
{
System.out.println("Please enter your bet:");
array[i]=input.nextLine();
}
System.out.println("This week wins, losses and ties loading...\n");
System.out.println("Result:");
for(int i = 0; i < 5; i++){
String randomResult = getRandomList();
System.out.print( randomResult + " ");
randomResultList.add ( randomResult );
}
System.out.println("\n\nYour bets were:");
for (int i = 0; i < 5; i++){
System.out.print(array[i] + " ");
}
//here is where you compare each result
for(int i = 0; i < 5; i++)
{
if( array[i].equals ( randomResultList.get ( i ) ))
{
score++;
}
}
System.out.println("\n\nYou were correct on: " + score + " bettings");
}
private static Random random = new Random();
public static String getRandomList() {
List<String> list = Arrays.asList("w", "l", "t");
int index = random.nextInt(list.size());
return list.get(index);
}
I/O Example:
Betting game initiating...
Type 'W' for win, 'L' for loss and 'T' for tie.
Please enter your bet:
w
Please enter your bet:
w
Please enter your bet:
w
Please enter your bet:
w
Please enter your bet:
w
This week wins, losses and ties loading...
Result:
l l l t w
Your bets were:
w w w w w
You were correct on: 1 bettings
Extra:
You could do all on the same iteration! check this out.
public static void main(String[] args) {
int score = 0;
// Win Loose or Tie
List<String> list = Arrays.asList("w", "l", "t");
Random rand = new Random ( );
//String with result and bets i.e (wwwww) and (wlltw). This avoid another iteration.
String result="";
String bets = "";
System.out.println("Betting game initiating... \nType 'W' for win, 'L' for loss and 'T' for tie.");
Scanner input = new Scanner(System.in);
for (int i = 0; i < 5; i++)
{
System.out.println("Please enter your bet:");
String bet =input.nextLine();
String randomResult = ( list.get ( rand.nextInt ( list.size ( ) ) ));
//concatenate String with results and bets with +=
result += randomResult;
bets += bet;
//check if u won
if( bet.equals ( randomResult ))
{
score++;
}
}
//This are just the results! no more iterations.
System.out.println("This week wins, losses and ties loading...\n");
System.out.println("Result:" + result);
System.out.println("\n\nYour bets were:" + bets );
System.out.println("\n\nYou were correct on: " + score + " bettings");
}

How to record array of ints, and print frequency of duplicates

Note: Just a practice problem, not for marks.
This is a practice problem given in a first year Java course:
Design and implement an application that reads an arbitrary number of integers, by the user, that are in the range 0 to 50 inclusive, and counts how many occurrences of each are entered. After all the input has been processed, print all of the values (with the number of occurrences) that were entered one or more times.
In addition, write a method that returns no value which would compute the average of the occurrences of all numbers entered by the user.
This is what I have (I have skipped the "average occurrence" part until I clean this up):
import java.util.Scanner;
public class Main
{
public static Scanner scan = new Scanner(System.in);
public static int[] userIntegers() // this method will build the array of integers, stopping when an out-of-range input is given
{
System.out.println("Enter the number of integers to be recorded: ");
int numInts = scan.nextInt();
int[] userArray = new int[numInts];
int i = 0;
while(i < numInts)
{
System.out.println("Enter an integer between 1-50 inclusive: ");
int userInteger = scan.nextInt();
if(isValidInteger(userInteger))
{
userArray[i] = userInteger;
i++;
}
else if(isValidInteger(userInteger) == false)
{
System.out.println("Try again.");
}
}
return userArray;
}
public static void occurrenceOutput(int[] input) // this method will print the occurrence data for a given array
{
int[] occurrenceArray = new int[51];
int j = 0;
while(j < 51) // iterates through all integers from 0 to 50, while the integer in the array is equal to integer j, the corresponding occurance array element increments.
{
for(int eachInteger : input)
{
occurrenceArray[j] = (eachInteger == j)? occurrenceArray[j]+=1: occurrenceArray[j];
}
j++;
}
int k = 0;
for(int eachOccurrence : occurrenceArray) // as long as there is more than one occurrence, the information will be printed.
{
if(eachOccurrence > 1)
{
System.out.println("The integer " + k + " occurrs " + eachOccurrence + " times.");
}
k++;
}
}
public static boolean isValidInteger(int userInput) // checks if a user input is between 0-50 inclusive
{
boolean validInt = (51 >= userInput && userInput >= 0)? true: false;
return validInt;
}
public static void main(String[] args)
{
occurrenceOutput(userIntegers());
}
}
Can someone point me in a more elegant direction?
EDIT: Thanks for the help! This is where I am at now:
import java.util.Scanner;
public class simpleHist
{
public static void main(String[] args)
{
getUserInputAndPrint();
getIntFreqAndPrint(intArray, numberOfInts);
}
private static int numberOfInts;
private static int[] intArray;
private static int[] intFreqArray = new int[51];
public static void getUserInputAndPrint()
{
// The user is prompted to choose the number of integers to enter:
Scanner input = new Scanner(System.in);
System.out.println("Enter the number of Integers: ");
numberOfInts = input.nextInt();
// The array is filled withchInteger = integer; integers ranging from 0-50:
intArray = new int[numberOfInts];
int integer = 0;
int i = 0;
while(i < intArray.length)
{
System.out.println("Enter integer value(s): ");
integer = input.nextInt();
if(integer > 50 || integer < 0)
{
System.out.println("Invalid input. Integer(s) must be between 0-50 (inclusive).");
}
else
{
intArray[i] = integer;
i++;
}
}
// Here the number of integers, as well as all the integers entered are printed:
System.out.println("Integers: " + numberOfInts);
int j = 0;
for(int eachInteger : intArray)
{
System.out.println("Index[" + j + "] : " + eachInteger);
j++;
}
}
public static void getIntFreqAndPrint(int[] intArray, int numberOfInts)
{
// Frequency of each integer is assigned to its corresponding index of intFreqArray:
for(int eachInt : intArray)
{
intFreqArray[eachInt]++;
}
// Average frequency is calculated:
int totalOccurrences = 0;
for(int eachFreq : intFreqArray)
{
totalOccurrences += eachFreq;
}
double averageFrequency = totalOccurrences / numberOfInts;
// Integers occurring more than once are printed:
for(int k = 0; k < intFreqArray.length; k++)
{
if(intFreqArray[k] > 1)
{
System.out.println("Integer " + k + " occurs " + intFreqArray[k] + " times.");
}
}
// Average occurrence of integers entered is printed:
System.out.println("The average occurrence for integers entered is " + averageFrequency);
}
}

You are actually looking for a histogram. You can implement it by using a Map<Integer,Integer>, or since the range of elements is limited to 0-50, you can use an array with 51 elements [0-50], and increase histogram[i] when you read i.
Bonus: understanding this idea, and you have understood the basics of count-sort

To calculate occurences, you can do something like this:
for(int eachInteger : input) {
occurrenceArray[eachInteger]++;
}
This will replace your while loop.