I'm doing a project for the university, and I need your help, because I don't find my wish in the API documentation.
I have a class named Belote.java (who simulate a card game).
My professor wants to force us to use the class Stack in a Vector (can't use another class sorry :/ )
Those two method set don't run, I think I know why, but I can't resolve this alone.
this.mainsJoueurs.set(numjoueur, this.mainsJoueurs.get(numjoueur).push(carte));
this.mainsJoueurs.set(numjoueur, this.mainsJoueurs.get(numjoueur).pop());
I put a commentary where the method bug.
package TP.TP5.Exercice2.Question2;
import java.util.Random;
import java.util.Vector;
import java.util.Stack;
import TP.TP5.Exercice1.Question4.Carte;
public class Belote {
private Stack<Carte> tasDistibution;
private Vector<Stack<Carte>> mainsJoueurs;
private Vector<Stack<Carte>> plisJoueurs;
public Belote() {
this.tasDistibution = new Stack<Carte>();
this.mainsJoueurs = new Vector<Stack<Carte>>(4);
this.plisJoueurs = new Vector<Stack<Carte>>(4);
for (int i = 0; i < 4; i++) {
this.mainsJoueurs.add(i, new Stack<Carte>());
this.plisJoueurs.add(i, new Stack<Carte>());
}
}
private void initialiserTasDistribution() {
for (int i = 1; i <= 4; i++) {
for (int j = 1; j <= 13; j++) {
if (j == 1 || (j >= 7 && j <= 13)) {
this.tasDistibution.push(new Carte(i, j));
}
}
}
}
private void couper() {
Stack<Carte> tas1 = new Stack<Carte>();
Stack<Carte> tas2 = new Stack<Carte>();
Random r = new Random();
int coupe = 1 + r.nextInt(33 - 1);
for (int i = 0; i < coupe; i++) {
Carte carte = this.tasDistibution.peek();
this.tasDistibution.pop();
tas1.push(carte);
}
while (tasDistibution.isEmpty() == false) {
Carte carte = this.tasDistibution.peek();
this.tasDistibution.pop();
tas2.push(carte);
}
while (tas1.isEmpty() == false) {
Carte carte = tas1.peek();
tas1.pop();
this.tasDistibution.push(carte);
}
while (tas2.isEmpty() == false) {
Carte carte = tas2.peek();
tas2.pop();
this.tasDistibution.push(carte);
}
}
private void melanger(int nbMelange) {
Carte tabcarte[] = new Carte[32];
for (int i = 0; i < tabcarte.length; i++) {
Carte cartesommet = this.tasDistibution.peek();
this.tasDistibution.pop();
tabcarte[i] = cartesommet;
}
for (int i = 0; i < nbMelange; i++) {
Random r = new Random();
int pos1 = 1 + r.nextInt(32 - 1);
int pos2 = 1 + r.nextInt(32 - 1);
if (pos1 == pos2) {
System.out.println("Pas de chance");
} else {
Carte temp;
temp = tabcarte[pos1];
tabcarte[pos1] = tabcarte[pos2];
tabcarte[pos2] = temp;
}
}
for (int i = 0; i < tabcarte.length; i++) {
Carte carte = tabcarte[i];
this.tasDistibution.push(carte);
}
}
private void donnerCartesAJoueur(int nbcartedonnes, int numjoueur) {
for (int i = 0; i < nbcartedonnes; i++) {
Carte carte = this.tasDistibution.peek();
this.tasDistibution.pop();
//My problem is right here, the method set doesn't work, because the method push return a "Carte" and not a "Stack<Carte>"
//The compilateur says : The method set(int, Stack<Carte>) in the type Vector<Stack<Carte>> is not applicable for the arguments (int, Carte)
this.mainsJoueurs.set(numjoueur, this.mainsJoueurs.get(numjoueur).push(carte));
}
}
private void distribuer() {
for (int i = 0; i < 4; i++) {
this.donnerCartesAJoueur(3, i);
}
for (int i = 0; i < 4; i++) {
this.donnerCartesAJoueur(2, i);
}
for (int i = 0; i < 4; i++) {
this.donnerCartesAJoueur(3, i);
}
for (int i = 0; i < 4; i++) {
System.out.println("\n\nDistribution pour joueur : " + (i + 1) + " \n\nMain du joueur : " + (i + 1));
this.mainsJoueurs.get(i).toString();
}
}
private void assemblerPlisJoueur() {
for (int i = 0; i < 4; i++) {
while (this.plisJoueurs.get(i).isEmpty() == false) {
Carte carte = this.plisJoueurs.get(i).peek();
//Same problem here
this.plisJoueurs.set(i, this.plisJoueurs.get(i).pop());
this.tasDistibution.push(carte);
}
}
}
private void preparerPremiereManche() {
this.initialiserTasDistribution();
this.melanger(32);
this.couper();
this.distribuer();
}
private void preparerMancheSuivante() {
this.assemblerPlisJoueur();
this.couper();
this.distribuer();
}
private void jouerPli() {
Stack < Carte > tasIntermediaire = new Stack<Carte>();
for (int i = 0; i < 4; i++) {
Carte carte = this.mainsJoueurs.get(i).peek();
//Same problem here
this.mainsJoueurs.set(i, this.mainsJoueurs.get(i).pop());
tasIntermediaire.push(carte);
}
Random r = new Random();
int gagnant = 0 + r.nextInt(4 - 0);
System.out.println("Le joueur " + (gagnant + 1) + " a gagné ce pli");
for (int i = 0; i < 4; i++) {
Carte carte = tasIntermediaire.peek();
tasIntermediaire.pop();
//Same problem here
this.plisJoueurs.set(gagnant, this.plisJoueurs.get(gagnant).push(carte));
}
System.out.println("Pli du joueur " + (gagnant + 1));
this.plisJoueurs.get(gagnant).toString();
}
private void jouerManche(int nbPlis) {
for (int i = 1; i <= nbPlis; i++) {
System.out.println("\n\nPli numéro : " + i);
this.jouerPli();
}
this.preparerMancheSuivante();
}
public void jouerPartie(int nbManches) {
this.preparerPremiereManche();
for (int i = 1; i <= nbManches; i++) {
System.out.println("\n\nManche numéro : " + i);
this.jouerManche(8);
}
System.out.println("Jeu terminé");
}
}
I don't know how to resolve this problem with using only the class Stack.
Everyone have an idea can be really nice :)
(Sorry for my bad English)
The problem is that you pass in the result of the push method, which is not a Stack<Carte>, but a Carte.
Stack<Carte> stack = this.mainsJoueurs.get(numjoueur);
stack.push(carte); // this returns the added element
this.mainsJoueurs.set(numjoueur, stack);
Related
can someone help me implement the maximum weight independent set for a TREE (not a graph)?
The tree is represented by an adjacency matrix, and we have an array for the weights of the vertices.
BFS output: // 0: distances from start vertex
// 1: BFS-order
// 2: parent-IDs
I tried this code, it doesn't work on all test cases and it says most of the time that the weight is too small.
Can someone help me find the errors?
import java.io.*;
import java.util.*;
public class Lab5
{
/**
* Problem: Find a maximum weight independent set using dynammic programming.
*/
private static int[] problem(Tree t, int[] weights)
{
// Implement me!
//base cases
if (t.noOfVertices==0) {
return new int[] {};
}
if (t.noOfVertices==1) {
return new int[] {weights[0]};
}
//we will implement this using bfs, we will use 0 as the root
int[][] bfs = t.bfs(0);
//finding leaves
int leaf[] = new int [t.noOfVertices];
//now we can implement our algorithm
//M is the maximum weight of the tree if it contains i, and M1 is the maximum weight of the tree if it doesn't contain i
int M[]=new int[t.noOfVertices];
int M1[]=new int[t.noOfVertices];
//treating elements that aren't leaves
int nodeDiscovered[] = new int[t.noOfVertices];
for (int i = 0; i<t.noOfVertices; i++) {
if (t.edges[i].length==1) {
leaf[i]=1;
M[i]=weights[i];
nodeDiscovered[i]=1;
M1[i]=0;
}
else {
leaf[i]=0;
nodeDiscovered[i]=0;
}
}
for (int i = 1; i<t.noOfVertices; i++) {
if (leaf[i]==1) {
int node = bfs[2][i];
if (nodeDiscovered[node]!=0) {
continue;
}
while (node>-1) {
int parent = bfs[2][node];
ArrayList<Integer> sibs = new ArrayList<Integer>();
if (parent!=-1) {
for (int j = 0; j<t.edges[parent].length; j++) {
if (t.edges[parent][j]!=bfs[2][parent]) {
sibs.add(t.edges[parent][j]);
}
}
}
else {
sibs.add(node);
}
for (int sib : sibs) {
if (nodeDiscovered[sib]!=0) {
continue;
}
M[sib]=weights[sib];
for (int k : t.edges[sib]) {
if(bfs[0][sib]==bfs[0][k]-1) {
M[sib]=M[sib]+M1[k];
M1[sib]+=(M[k]>M1[k])?M[k]:M1[k];
}
}
nodeDiscovered[sib]=1;
}
node = bfs[2][node];
}
}
}
//putting the answers in an arraylist
ArrayList<Integer> set = new ArrayList<Integer>();
if (M[0]>M1[0]) {
set.add(0);
}
for (int i = 1; i<t.noOfVertices; i++) {
if (!set.contains(bfs[2][i]) && M[i]>=M1[i] ) {
set.add(i);
}
}
System.out.println(set);
//putting the elements of the arraylist into an array of int
int[] set1 = new int[set.size()];
for (int i = 0; i<set.size(); i++) {
set1[i]=set.get(i);
}
return set1;
}
// ---------------------------------------------------------------------
// Do not change any of the code below!
// Do not change any of the code below!
/**
* Determines if a given set of vertices is an independent set for the given tree.
*/
private static boolean isIndSet(Tree t, int[] set)
{
if (set == null) return false;
boolean[] covered = new boolean[t.noOfVertices];
for (int i = 0; i < set.length; i++)
{
int vId = set[i];
int[] neighs = t.edges[vId];
if (covered[vId]) return false;
covered[vId] = true;
for (int j = 0; j < neighs.length; j++)
{
int nId = neighs[j];
covered[nId] = true;
}
}
return true;
}
private static final int LabNo = 5;
private static final String course = "CS 427";
private static final String quarter = "Fall 2021";
private static final Random rng = new Random(190817);
private static boolean testProblem(int[][] testCase)
{
int[] parents = testCase[0];
int[] weights = testCase[1];
Tree t = Tree.fromParents(parents);
int[] solution = maxIsWeight(t, weights);
int isWeight = solution[0];
int isSize = solution[1];
int[] answer = problem(t, weights.clone());
if (!isIndSet(t, answer))
{
System.out.println("Not an independent set.");
return false;
}
int ansWeight = 0;
for (int i = 0; i < answer.length; i++)
{
ansWeight += weights[answer[i]];
}
if (ansWeight < isWeight)
{
System.out.println("Weight too small.");
return false;
}
if (answer.length < isSize)
{
System.out.println("Set too small.");
return false;
}
return true;
}
private static int[] maxIsWeight(Tree t, int[] weigh)
{
int n = t.noOfVertices;
int[][] dfs = t.dfs(0);
int[] post = dfs[2];
int[] w = new int[n];
for (int i = 0; i < n; i++)
{
w[i] = weigh[i] * n + 1;
}
boolean[] isCandidate = new boolean[n];
for (int i = 0; i < n; i++)
{
int vId = post[i];
if (w[vId] <= 0) continue;
isCandidate[vId] = true;
int[] neighs = t.edges[vId];
for (int j = 0; j < neighs.length; j++)
{
int uId = neighs[j];
w[uId] = Math.max(w[uId] - w[vId], 0);
}
}
int isWeight = 0;
int isSize = 0;
for (int i = n - 1; i >= 0; i--)
{
int vId = post[i];
if (!isCandidate[vId]) continue;
isWeight += weigh[vId];
isSize++;
int[] neighs = t.edges[vId];
for (int j = 0; j < neighs.length; j++)
{
int uId = neighs[j];
isCandidate[uId] = false;
}
}
return new int[] { isWeight, isSize };
}
public static void main(String args[])
{
System.out.println(course + " -- " + quarter + " -- Lab " + LabNo);
int noOfTests = 300;
boolean passedAll = true;
System.out.println("-- -- -- -- --");
System.out.println(noOfTests + " random test cases.");
for (int i = 1; i <= noOfTests; i++)
{
boolean passed = false;
boolean exce = false;
try
{
int[][] testCase = createProblem(i);
passed = testProblem(testCase);
}
catch (Exception ex)
{
passed = false;
exce = true;
ex.printStackTrace();
}
if (!passed)
{
System.out.println("Test " + i + " failed!" + (exce ? " (Exception)" : ""));
passedAll = false;
//break;
}
}
if (passedAll)
{
System.out.println("All test passed.");
}
}
private static int[][] createProblem(int testNo)
{
int size = rng.nextInt(Math.min(testNo, 5000)) + 5;
// -- Generate tree. ---
int[] parents = new int[size];
parents[0] = -1;
for (int i = 1; i < parents.length; i++)
{
parents[i] = rng.nextInt(i);
}
// -- Generate weights. ---
int[] weights = new int[size];
for (int i = 0; i < weights.length; i++)
{
weights[i] = rng.nextInt(256);
}
return new int[][] { parents, weights };
}
}
I attached an image that contains the algorithm that I used.
I'm creating an UNO project and am a bit confused about how to assign the drivers to my DiscardPile class.
Thank you in advance for any answers you may give.
Sincerely,
Jayda M
I've asked my fellow students for assistance and have scoured the internet for anything that could be helpful with no luck. My professor isn't helpful at all haha
This is the full code for the Driver.java file. If you need me to give you any of the others I have no problem doing so.
package unoGame;
import java.util.Random;
//import java.util.Collections;
public class Driver {
public static unoDeck theDeck = new unoDeck();
public static PlayerHand[] thePlayers;
public static DiscardPile dp = new DiscardPile();
public static int nextPlayer;
public static Random getRandom = new Random();
public static void main(String[] args) {
// TODO Auto-generated method stub
thePlayers = new PlayerHand[3];
thePlayers[0] = new PlayerHand("name 1");
thePlayers[1] = new PlayerHand("name 2");
thePlayers[2] = new PlayerHand("name 3");
theDeck.shuffle();
System.out.println("Here is the Deck: " + theDeck);
System.out.println(" Welcome to UNO! ");
if (dp.isEmpty()) {
System.out.println(" Discard is Empty ");
}
else {
System.out.println(" Not Empty ");
}
for (int i = 0; i < 7; i++) {
for (int j = 0; j < thePlayers.length; j++) {
thePlayers[j].addCard(theDeck.deal());
}
}
nextPlayer = 0;
showPlayers();
dp.addCard(theDeck.deal());
while (checkForWin() == false) {
findNextPlayer();
if (theDeck.isEmpty()) {
theDeck.replenish(dp.clear());
}
playerTurn();
}
System.out.println(thePlayers[nextPlayer], getName() + " Wins!")
}
public static void showPlayers() {
for (PlayerHand p : thePlayers)
System.out.println(p);
}
public static boolean checkForWin() {
if (p.isWin()) {
win = true;
}
return win;
}
public static void findNextPlayer() {
nextPlayer++;
nextPlayer = nextPlayer % thePlayers.length;
if(dp.getTopCard().getValue()=="SK") {
nextPlayer++;
nextPlayer = nextPlayer % thePlayers.length;
}
if(dp.getTopCard().getValue() == "D2") {
for(int i = 0; i <= 1; i++) {
thePlayers[nextPlayer].addCard(theDeck.deal());
}
}
if(dp.getTopCard().getValue() == "W4") {
for(int i = 0; i <= 3; i++) {
thePlayers[nextPlayer].addCard(theDeck.deal());
}
}
if(dp.getTopCard().getValue() == "RV") {
for(int i = 0; i < thePlayers.length / 2; i++) {
PlayerHand rev = thePlayers[i];
thePlayers[i] = thePlayers[thePlayers.length - i -1];
rev = thePlayers[thePlayers.length - i -1];
if(nextPlayer == 0) {
nextPlayer = 0;
}
if(nextPlayer == 2) {
nextPlayer = 1;
}
}
nextPlayer++;
}
}
public static void playerTurn() {
if (thePlayers[nextPlayer].hasMatch(dp.getTopCard())) {
System.out.println(thePlayers[nextPlayer].getName() + " has a match!");
unoCard c = thePlayers[nextPlayer].playCard(dp.getTopCard());
dp.addCard(c);
if(c.getValue().equals("W")) {
c.setColor(theDeck.newColor());
}
if(c.getValue().equals("W4")) {
c.setColor(theDeck.newColor());
}
System.out.println(thePlayers[nextPlayer].getName() + " played a: " dp.getTopCard());
System.out.println(thePlayers[nextPlayer]);
}
else {
unoCard c = theDeck.deal();
thePlayers[nextPlayer]c.addCard(c);
System.out.println(thePlayers[nextPlayer].getName() + " drew a: " + c);
}
}
}
There are errors are on these lines of code: 46, 50, 57, 58, 60, 106 and 111. Most of them are saying they're undefined, and I'm unsure of where to do so amongst my files. I'm expecting the Driver to run the game as a whole, so because it's gone wack I can't run the build properly. If you need more information to work with, I'll gladly give it to you!
EDIT:
The lines and/or words where the errors are taking place have asterisks around them
The error descriptions with their corresponding lines
The printed console error after running Driver. Hopefully this works for the Reproducible Example required :)
Here is your Driver class with compilation problems fixed. I suggest you compare it with your current code in order to see what I changed.
I also needed to add method replenish() in class unoDeck because it didn't exist and is called from class Driver. Right now that method does nothing. As I said, I only added it in order to fix the compilation error.
package unoGame;
import java.util.Random;
public class Driver {
public static unoDeck theDeck = new unoDeck();
public static PlayerHand[] thePlayers;
public static DiscardPile dp = new DiscardPile();
public static int nextPlayer;
public static Random getRandom = new Random();
public static void main(String[] args) {
thePlayers = new PlayerHand[3];
thePlayers[0] = new PlayerHand("name 1");
thePlayers[1] = new PlayerHand("name 2");
thePlayers[2] = new PlayerHand("name 3");
theDeck.shuffle();
System.out.println("Here is the Deck: " + theDeck);
System.out.println(" Welcome to UNO! ");
if (dp.isEmpty()) {
System.out.println(" Discard is Empty ");
}
else {
System.out.println(" Not Empty ");
}
for (int i = 0; i < 7; i++) {
for (int j = 0; j < thePlayers.length; j++) {
thePlayers[j].addCard(theDeck.deal());
}
}
nextPlayer = 0;
showPlayers();
dp.addCard(theDeck.deal());
while (checkForWin() == false) {
findNextPlayer();
if (theDeck.isEmpty()) {
theDeck.replenish(dp.clear());
}
playerTurn();
}
System.out.println(thePlayers[nextPlayer].getName() + " Wins!");
}
public static void showPlayers() {
for (PlayerHand p : thePlayers)
System.out.println(p);
}
public static boolean checkForWin() {
boolean win = false;
if (thePlayers[nextPlayer].isWin()) {
win = true;
}
return win;
}
public static void findNextPlayer() {
nextPlayer++;
nextPlayer = nextPlayer % thePlayers.length;
if (dp.getTopCard().getValue() == "SK") {
nextPlayer++;
nextPlayer = nextPlayer % thePlayers.length;
}
if (dp.getTopCard().getValue() == "D2") {
for (int i = 0; i <= 1; i++) {
thePlayers[nextPlayer].addCard(theDeck.deal());
}
}
if (dp.getTopCard().getValue() == "W4") {
for (int i = 0; i <= 3; i++) {
thePlayers[nextPlayer].addCard(theDeck.deal());
}
}
if (dp.getTopCard().getValue() == "RV") {
for (int i = 0; i < thePlayers.length / 2; i++) {
PlayerHand rev = thePlayers[i];
thePlayers[i] = thePlayers[thePlayers.length - i - 1];
rev = thePlayers[thePlayers.length - i - 1];
if (nextPlayer == 0) {
nextPlayer = 0;
}
if (nextPlayer == 2) {
nextPlayer = 1;
}
}
nextPlayer++;
}
}
public static void playerTurn() {
if (thePlayers[nextPlayer].hasMatch(dp.getTopCard())) {
System.out.println(thePlayers[nextPlayer].getName() + " has a match!");
unoCard c = thePlayers[nextPlayer].playCard(dp.getTopCard());
dp.addCard(c);
if(c.getValue().equals("W")) {
c.setColor(theDeck.newColor());
}
if(c.getValue().equals("W4")) {
c.setColor(theDeck.newColor());
}
System.out.println(thePlayers[nextPlayer].getName() + " played a: " + dp.getTopCard());
System.out.println(thePlayers[nextPlayer]);
}
else {
unoCard c = theDeck.deal();
thePlayers[nextPlayer].addCard(c);
System.out.println(thePlayers[nextPlayer].getName() + " drew a: " + c);
}
}
}
Hi Guys i have a problem in my program of Totoloto. I want create a function for show the six numbers of the key but i can't because in my output show only a one number at end counter position. I make a debug with System.out.println in inside the function numeDeChaves and appears all numbers . If try without functions and its work but i want in function for legible code and learn a little more how to work the functions.
this is wrong output:
Quantas chaves pretende gerar? 6
As chaves geradas são: 1ª chave -> 2ª chave -> 3ª chave -> 4ª chave -> 5ª chave -> 6ª chave -> 36
public static void main(String[] args) {
System.out.println("Totoloto \n");
System.out.println("Quantas chaves pretende gerar?");
int numero = Ler.umInt();
int[] numeroChaves = new int[numero];
int[] chave = new int[8];
System.out.println("");
System.out.println("As chaves geradas são: ");
System.out.println(numeroDeChaves(numeroChaves));
}
public static int numeroDeChaves(int[] numeroChaves){
int contador = 1;
int totalChaves = 0;
for (int i = 0; i < numeroChaves.length; i++) {
System.out.print(contador + "ª chave -> ");
contador++;
for (int j = 0; j < numeroChaves.length; j++) {
numeroChaves[j] = chaveAleatoria(numeroChaves);
totalChaves = numeroChaves[j];
}
System.out.println("");
}
return totalChaves;
}
public static int chaveAleatoria(int chave[]) {
int numeroAleatorio = (int) (Math.random() * 43) + 6;
int ultimoNumero = chave[0] + 1;
int chaveGerada = 0;
int contarChaves = 0;
for (int i = 1; i < chave.length; i++) {
if (chave[i] == chave[i - 1] && ultimoNumero != chave[i - 1]) {
ultimoNumero = chave[i];
chave[i] = numeroAleatorio;
} else {
chave[i] = numeroAleatorio;
chaveGerada = chave[i];
System.out.print("");
}
}
return chaveGerada;
}
I have a doubt in deleting all elements by number in array of objects in Java, it will not be recommended to use ArrayList, the method works but only that it does not eliminate some elements leaving some elements modified, because of their positions in the array
class Pack
public class Pack {
static int nextNumber = 0;
int number;
String name;
public Pack(String name) {
this.number = ++nextNumber;
this.name = name;
}
#Override
public String toString() {
return "Pack ID:" + number + " - Name: " + name;
}
}
class Container
class Container {
static int nextNumber = 0;
int number;
int qtPack;
Pack[] packs;
public Container() {
this.number = ++nextNumber;
this.qtPack = 0;
this.packs = new Pack[10];
}
public boolean addPack(Pack pack) {
packs[qtPack] = pack;
qtPack++;
return true;
}
public Pack removePack(int numberPack) {
int idx;
Pack removePack = null;
idx = indexOfPackByID(numberPack);
if (idx != -1) {
removePack = packs[idx];
if (removePack != null) {
for (int i = idx; i < qtPack - 1; i++) {
packs[i] = packs[i + 1];
}
qtPack--;
}
}
return removePack;
}
private int indexOfPackByID(int numberPack) {
for (int i = 0; i < qtPack; i++) {
if ((packs[i] != null)
&& (packs[i].number == numberPack)) {
return i;
}
}
return -1;
}
}
class Main
public class Main {
public static void main(String[] args) {
Pack[] packs = new Pack[5];
packs[0] = new Pack("A");
packs[1] = new Pack("B");
packs[2] = new Pack("C");
packs[3] = new Pack("D");
packs[4] = new Pack("E");
Container container = new Container();
for (int i = 0; i < packs.length; i++) {
container.addPack(packs[i]);
}
System.out.println("--- PACK IN CONTAINER ---");
for (int i = 0; i < container.qtPack; i++) {
System.out.println(container.packs[i].toString());
}
System.out.println("\n--- REMOVE PACK ---");
for (int i = 0; i < container.qtPack; i++) {
Pack pack = container.removePack(container.packs[i].number);
System.out.println("Remove " + pack.name+" - ID: "+pack.number);
}
}
}
the output from Main
--- PACK IN CONTAINER ---
Pack ID:1 - Name: A
Pack ID:2 - Name: B
Pack ID:3 - Name: C
Pack ID:4 - Name: D
Pack ID:5 - Name: E
--- REMOVE PACK ---
Remove A - ID: 1
Remove C - ID: 3
Remove E - ID: 5
any suggestion?
You could either remove them from the end...
for (int i = container.qtPack-1; i >= 0; i--) {
Pack pack = container.removePack(container.packs[i].number);
System.out.println("Remove " + pack.name+" - ID: "+pack.number);
}
...or always remove the first element:
int count = container.qtPack;
for (int i = 0; i < count; i++) {
Pack pack = container.removePack(container.packs[0].number);
System.out.println("Remove " + pack.name+" - ID: "+pack.number);
}
This is because by changing the array you are changing the condition (here container.packs and container.qtPack) with each iteration. Keep in mind that the loop condition i < container.qtPack is evaluated for each iteration.
Take a closer look at Container.removePack()
for (int i = idx; i < qtPack - 1; i++) {
packs[i] = packs[i + 1];
}
Each time invoke removePack(), the container references some elements of packs[] to the 'next' Pack. So the packs[] are not the same after removePack().
I want to create a class that creates a Matrix via an ArrayList.
So that's what I did:
public class Matrice implements IMatrice {
ArrayList elements;
private int numLignes;
private int numColonnes;
public static void main(String[] args) {
Matrice test = new Matrice(3, 4, 6.0);
System.out.println(test);
}
public Matrice (int numLignes, int numColonnes, double valeur){
this.numLignes = numLignes;
this.numColonnes = numColonnes;
elements = new ArrayList(numLignes * numColonnes);
for(int i = 0; i < numLignes * numColonnes; i++){
elements.add(i, valeur);
}
}
}
Now that i created this, I wanted to try if it works. Then I created this toString() method:
public String toString() {
final DecimalFormat DEC_FORMAT = new DecimalFormat("0.0");
final int ESP = 8;
int num;
String sTmp;
String s = "[";
for (int i = 0 ; i < (numLignes * numColonnes) ; i++) {
//etendre i sur ESP colonnes
sTmp = "";
num = ESP - DEC_FORMAT.format(elements.get(i)).length();
for (int j = 0 ; j < num ; j++) {
sTmp = sTmp + " ";
}
sTmp = sTmp + DEC_FORMAT.format(elements.get(i));
if (i != 0 && i % numColonnes == 0) {
s = s + " ]\n[" + sTmp;
} else {
s = s + sTmp;
}
}
s = s + " ]";
return s;
}
Then this is my main to try the Matrix:
public static void main(String[] args) {
Matrice test = new Matrice(3, 4, 6.0);
System.out.println(test);
}
and i don't know why but i only get this :
[ ]
I know that a little thing is wrong but I can't find what. Could you help me?
Okay, i messed up...
The problem was in here :
elements.add(i, valeur);
i did a mistake... i mingled with the set() method.
here is the correction :
elements.add(valeur);