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I'm trying to make a java array code

i'm trying to build a code for different actions in arrays with different methods (Constructors) but i cannot seem to find a way to link them...I've made a array with 100 elements and a random variable to fill it....i'd like to know how to get my random elements from the first methods to the second one to make the comparing.... and also i'd like to not include in the 0 element in the random generator..any help?
this is my code
import java.util.*;
public class prova1{
public int min;
public void tabele(){
Random r = new Random();
int d;
int e[]= new int[100];
for(int i=0; i<e.length;i++){
d=r.nextInt(100);
e[i]=d;
System.out.println(e[i]);
}
}
public void emin(){
Random r = new Random();
int d;
int e[]=new int[100];
for(int i=0; i<e.length;i++){
d=r.nextInt(100);
e[i]=d;
if(e[i]<min){
min=e[i];
}
}
System.out.println("Vlera me e vogel eshte: " +min);
}
public static void main(String []args){
prova1 prova = new prova1();
prova.tabele();
prova.emin();
}
}

Return the array from tabele to a local variable and send it as parameter to emin
import java.util.*;
public class prova1 {
public int min;
public int[] tabele() {
Random r = new Random();
int d;
int e[]= new int[100];
for(int i=0; i<e.length;i++){
d=r.nextInt(99) + 1;
e[i]=d;
System.out.println(e[i]);
}
return e;
}
public void emin(int[] e) {
Random r = new Random();
int d;
for(int i=0; i<e.length;i++) {
if(e[i]<min) {
min=e[i];
}
}
System.out.println("Vlera me e vogel eshte: " +min);
}
public static void main(String []args){
prova1 prova = new prova1();
int[] arr = prova.tabele();
prova.emin(arr);
}
}

Displaying a shuffled integer array in java

sorry I'm really new to all of this. I know this is a stupid/easy question, but how would I display the shuffled array after i've set it all up. I have my code below and made the class that creates the array and has the algorithm for shuffling the integers inside the array. But I can't figure out how to display the shuffled array. Heres my code below:
My main:
package lab4b;
import java.util.Scanner;
public class Lab4B {
public static void main(String[] args) {
Shuffler test = new Shuffler(15);
test.Shuffle();
test.display();
}
}
and my Shuffle class:
package lab4b;
import java.security.SecureRandom;
public class Shuffler {
private static final SecureRandom randomNumbers = new SecureRandom();
private int [] data;
public Shuffler (int size){
data = new int [size];
for(int i = 0; i<data.length;i++){
data[i]= i+1;
}
}
public void Shuffle(){
int temp;
for(int first = 0; first<data.length; first++){
int second = randomNumbers.nextInt(data.length);
temp = data[first];
data[first] = data[second];
data[second] = temp;
}
}
public void display()
{
for(int counter =0; counter<data.length; counter++ ){
System.out.print(data[counter]+ " ");
}
System.out.println();
}
}

In this loop you are reset the value of the dataarray
for(int counter =0; counter<data.length; counter++ ){
// data[counter] = counter + 1; - do not do this
System.out.print(data[counter]+ " ");
}

Recursive Coin Change Making by printing all possible ways

I have tried to print all the paths which give the given amount. But my code does not work properly. I think I am missing some points to print all possible combinations. For example;
if amount: 7 and startCoin = 25, the program needs to give me:
{5,1,1} and {1,1,1,1,1,1,1}.
Can you help me to fix these problem?
Note: Preferably Java Solutions
class Solution {
static int[] coinSet = {1,5,10,25};
static List<List<Integer>> possibleWays = new ArrayList<>();
static List<Integer> currentWay = new ArrayList<>();
private static int makeChange(int amount, int startCoin){
boolean flag = false;
for(int i =0 ; i < coinSet.length ; i++){
if(coinSet[i] == startCoin) {
flag =true;
}
}
if(!flag){
throw new IllegalArgumentException("startCoin has to be in the specified range");
}
int nextCoin = 0;
switch(startCoin) {
case 25:
nextCoin = 10;
break;
case 10:
nextCoin = 5;
break;
case 5:
nextCoin = 1;
break;
case 1:
possibleWays.add(currentWay);
currentWay = new ArrayList<>();
return 1;
}
int ways = 0;
for(int count = 0; count * startCoin <= amount; count++){
ways += makeChange(amount - (count * startCoin),nextCoin);
}
return ways;
}
public int calculateNumberOfWays(int amount, int startCoin) throws Exception {
if (amount == 0) {
throw new Exception(); }
return makeChange(amount, startCoin);
}
public static void main(String[] args) {
System.out.println(makeChange(5,25));
System.out.println(possibleWays);
}
}

This can be solved using backtracking but that is not very efficient, below is the working java code
/**
* Created by sumit sharma on 3/1/2016.
*/
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Random;
public class Main {
static int[] coinSet = {1,5,10,25};
static List<List<Integer>> possibleWays = new ArrayList<>();
static List<Integer> currentWay = new ArrayList<>();
public static void main(String[] args) {
List<Integer> countOfCoins = new ArrayList<>();
makeChange(7, 0, countOfCoins);
//System.out.print(possibleWays);
}
private static int makeChange(int amount, int startCoinIdx, List<Integer> coinsSoFar) {
if(startCoinIdx == coinSet.length){
if(amount == 0){
possibleWays.add(coinsSoFar);
System.out.println(coinsSoFar);
}
//System.out.println(coinsSoFar);
return 0;
}
for(int count = 0;(count*coinSet[startCoinIdx]) <= amount;count++){
List<Integer> temp = new ArrayList<>();
for(int i = 0;i < coinsSoFar.size();i++) temp.add(coinsSoFar.get(i));
for(int i = 0;i < count;i++) temp.add(coinSet[startCoinIdx]);
makeChange(amount - (count * coinSet[startCoinIdx]),startCoinIdx+1, temp);
temp.clear();
}
return 0;
}
}
Link to solution on Ideone : http://ideone.com/kIckmG

Returning the largest number from random numbers

I have managed to print 200 random numbers, from those numbers I want the program to return the largest number out of it.
import java.util.Random;
class random {
public static int genRandom() {
return new Random().nextInt(1000000);
}
public static void main(String[] args) {
Random ran = new Random();
for (int i = 0; i < 200; i++) {
System.out.println(ran.nextInt(1000000));
}
}
}

Not the best answer but according to your code you can use :
static int maxNumber = 0;
public static int genRandom() {
return new Random().nextInt(1000000);
}
public static void main(String[] args) {
for (int i = 0; i < 200; i++) {
int randomNumber = genRandom();
if (randomNumber > maxNumber) {
maxNumber = randomNumber;
}
System.out.println(randomNumber);
}
System.out.println("The largest number is: " + maxNumber);
}

Java Code
public class TestProgram {
public static void main(String[] args) throws FileNotFoundException {
Random ran = new Random();
ArrayList<Integer> randNum = new ArrayList<Integer>();
for (int i = 0; i < 200; i++) {
//System.out.println(ran.nextInt(1000000));
randNum.add(ran.nextInt(1000000));
}
//System.out.print(randNum);
Collections.sort(randNum);
System.out.println(randNum);
System.out.println("Largest Number is " + randNum.get(randNum.size()-1));
}
}

What am I doing wrong with using arrays?

I'm trying to fill an array using a method and later print that array out.
However when I try to do so all it gives me are zeroes. I think my fill method is not working properly but I'm not sure why. I'm trying to understand arrays but so far no good. I would prefer an explanation rather than an answer. If I can get this myself it would be best.
import java.util.Scanner;
public class diverScore {
static double score = 0;
static double validDegreeOfDiff = 0;
public static void main(String[] args) {
double[] score = new double[6];
inputAllScores(score);
printArray(score);
}
public static double[] inputAllScores(double[] x) {
Scanner s = new Scanner(System.in);
double[] array_score = new double[6];
for (int i = 0; i < 6; i++) {
System.out.println("What is the score given by the judge?");
array_score[i] = s.nextDouble();
}
return array_score;
}
public static void printArray(double[] j) {
for (int i = 0; i < 6; i++) {
System.out.println("The array is:" + j[i]);
}
}
}

In your inputAllScores, you're writing to a new local array, and returning it, but you're not using the returned array. It would be better if you wrote to the array that you passed into that method (which inside the method is called x).

try
import java.util.Scanner;
public class DiverScore {
static double score = 0;
static double validDegreeOfDiff = 0;
public static void main(String[] args) {
// double[] score = new double[6];
double[] score = inputAllScores(/*score*/);
printArray(score);
}
public static double[] inputAllScores(/*double[] x*/) {
Scanner s = new Scanner(System.in);
double[] array_score = new double[6];
for (int i = 0; i < 6; i++) {
System.out.println("What is the score given by the judge?");
array_score[i] = s.nextDouble();
}
return array_score;
}
public static void printArray(double[] j) {
for (int i = 0; i < 6; i++) {
System.out.println("The array is:" + j[i]);
}
}
}

double[] score = new double[6];
This line simply initializes an array of type double with 6 indexes allocated for it, with each resulting in 0 when printed out.
You could simply change the code in main to this, thus actually using the return value of the inputAllScores function.
public static void main(String[] args) {
double[] score = new double[6];
printArray(inputAllScores(score));
}
HTH