I apologies for my poor knowledge of programming and english in advance.
So my friends and I are a creating a tower defence game as our 2nd semester project at our university. The semester is about user involvment, so we decided to create a tower defence as we can include user in a lot of things. But we have given our tower defence game a twist, we have included questions inbetween waves, which gives a reward of x amount of gold if answered correct.
As it is right now we only have one question for each wave, and we would like to include up to 5 questions for each wave, this is done due to if people want to play it more than once, they cannot just remember the right answer from earlier. We have already made a list of questions in a text file which looks like this, example:
Which Chinese leader’s widow was sentenced to death as a member of the Gang of Four?
A: Zhou Enlai
B: Jiang Zemin
C: Mao Zedong
D: Sun Yat-Sen
3
Example done, and this is done with up to 50 questions.
And our code for reading this txt file so far looks like this:
public class ReadFile {
public static void OpenFile(){
try {
FileReader fr = new FileReader("/save/QuestionsB.txt");
BufferedReader textReader = new BufferedReader(fr);
//int numberOfLines = readLines();
for (int j=0; j < Value.numberOfQuestions; j++){
for (int i=0; i<5; i++){
Value.textData[j][i] = textReader.readLine();
}
}
textReader.close();
}
catch (IOException ex) {
Logger.getLogger(ReadFile.class.getName()).log(Level.SEVERE, null, ex);
}
}
public static void loadQuestions(){
try {
Scanner loadScanner = new Scanner(new File("save/questionFile.qreepz"));
while (loadScanner.hasNextLine()) {
for (int j=0; j < Value.numberOfQuestions; j++){
for (int i=0; i<6; i++){
Value.textData[j][i] = loadScanner.nextLine();
}
}
}
loadScanner.close();
} catch (Exception e) { }
}
My question is now, how do we create a game with 5 questions saved for eachwave, and one random is selected, I hope you know what I mean.
I was thinking about doing some kind of if loop, but I am not sure of how to do this. I hope you can help, thank you for your time!
Here is some code to get you started. I'll leave it to you as to how and where to place it.
Question[] possibleQuestions = //collate your questions into an array.
Random rand = new Random();
Question thisRoundsQuestion = possibleQuestions[rand.nextInt(possibleQuestions.length)];
//offer question to user.
Info on Random.nextInt() can be found here.
This solution does not cover repeating questions. If you would like to never repeat a question you will either need to keep track of the Questions asked or use a Collection such as an ArrayList and remove Questions as you use them to make sure they're not in the pool next time around.
Related
I'm fairly new to coding and am struggling with an assignment for my class. The program takes a user input for the size of an Array and prompts the user to enter each value 1 at a time. The array size starts at 3 and if the array needs to be bigger when the array has filled a new array that's 2x size is created and all info is copied into it. I was able to figure out this part but I just can't see what I'm doing wrong in the downsizing part. After the info is copied I have to remove the trailing zeroes. I think I have the downsize method right but I don't know if I'm calling it right
import java.util.Scanner;
public class Lab6 {
public static void main(String args[]) {
int[] myarray = new int[3];
int count = 0;
int limit, limitcount = 1;
Scanner kbd = new Scanner(System.in);
System.out.print("How many values would you like to enter? ");
limit = kbd.nextInt();
while (limitcount <= limit) {
System.out.println("Enter an integer value ");
int input = kbd.nextInt();
limitcount++;
if (count < myarray.length) {
myarray[count] = input;
}
else {
myarray = upsize(myarray);
myarray[count] = input;
}
count++;
}
myarray = downsize(myarray, count)
printArray(myarray);
System.out.println("The amount of values in the arrays that we care about is: " + count);
}
static int[] upsize(int[] array) {
int[] bigger = new int[array.length * 2];
for (int i =0;i<array.length; i++) {
bigger[i] = array[i];
}
return bigger;
}
static void printArray( int[] array ) {
for ( int number : array ) {
System.out.print( number + " ");
}
System.out.println();
}
static int[] downsize(int[] array,int count) {
int[] smaller = new int[count];
for (int i =0; i<count; i++) {
smaller[i] = array[i];
}
return array;
}
}
Giving you a full response rather than a comment since you're new here and I don't want to discourage you with brevity which could be misunderstood.
Not sure what happened to your code when you pasted it in here, you've provided everything but the format is weird (the 'code' bit is missing out a few lines at the top and bottom). Might be one to double-check before posting. After posting, I see that someone else has already edited your code to fix this one.
You're missing a semi-colon. I'm not a fan of handing out answers, so I'll leave you to find it :) If you're running your code in an IDE, it should already be flagging that one up for you. If you're not, why on earth not??? IntelliJ is free, easy to get going with, and incredibly helpful. There are others out there as well which different folk prefer :) An IDE will help you spot all sorts of useful things quickly.
I have now run your code, and you do have a problem! It's in your final method, downsize(). Look very, very carefully at the return statement ;) Your questions suggests you aren't actually sure whether or not this method is right, which makes me wonder: have you actually run this code with different inputs to see what results you get? Please do that.
Style-wise: blank lines between methods would make the code easier to look at, by providing a visual gap between components. Please be consistent with putting your opening { on the same line as the method signature, and with having spaces between items, e.g. for (int i = 0; i < count; i++) rather than for (int i =0; i<count; i++). The compiler couldn't care less, but it is easier for humans to look at and just makes it look like you did care. Always a good thing!
I think it is awesome that you are separating some of the work into smaller methods. Seriously. For extra brownie points, think about how you could move that while() block into its own method, e.g. private int[] getUserData(int numberOfItems, Scanner scanner). Your code is great without this, but the more you learn to write tiny units, the more favours you will be doing your future self.
Has your class looked at unit testing yet? Trust me, if not, when you get to this you will realise just how important point 5 can be. Unit tests will also help a lot with issues such as the one in point 3 above.
Overall, it looks pretty good to me. Keep going!!!
Simple mistake in your downsize method. If you have an IDE like Eclipse, Intellij, etc. you would have seen it flagged right away.
return array; // should return smaller
I have a few suggestions since you mentioned being new to coding.
The "limitcount" variable can be removed and substituted with "count" at every instance. I'll leave it to you to figure that out.
Try using more descriptive and understandable variable names. Other people will read your code (like now) and appreciate it.
Try to use consistent spacing/indentation throughout your code.
Your upsize method can be simplified using a System.arraycopy() call which generally performs better and avoids the need for writing out a for loop. You can rewrite downsize in a similar manner.
static int[] upsize(int[] array) {
int[] bigger = new int[array.length * 2];
System.arraycopy(array, 0, bigger, 0, array.length);
return bigger;
}
Edit: All good points by sunrise above - especially that you've done well given your experience. You should set up an IDE when you have the time, they're simple to use and invaluable. When you do so you should learn to step through a debugger to explore the state of your program over time. In this case you would have noticed that the myarray variable was never reassigned after the downsize() call, quickly leading you to a solution (if you had missed the warning about an unused "smaller" array).
So, I've searched around stackoverflow for a bit, but I can't seem to find an answer to this issue.
My current homework for my CS class involves reading from a file of 5000 random numbers and doing various things with the data, like putting it into an array, seeing how many times a number occurs, and finding what the longest increasing sequence is. I've got all that done just fine.
In addition to this, I am (for myself) adding in a method that will allow me to overwrite the file and create 5000 new random numbers to make sure my code works with multiple different test cases.
The method works for the most part, however after I call it it doesn't seem to "activate" until after the rest of the program finishes. If I run it and tell it to change the numbers, I have to run it again to actually see the changed values in the program. Is there a way to fix this?
Current output showing the delay between changing the data:
Not trying to change the data here- control case.
elkshadow5$ ./CompileAndRun.sh
Create a new set of numbers? Y for yes. n
What number are you looking for? 66
66 was found 1 times.
The longest sequence is [606, 3170, 4469, 4801, 5400, 8014]
It is 6 numbers long.
The numbers should change here but they don't.
elkshadow5$ ./CompileAndRun.sh
Create a new set of numbers? Y for yes. y
What number are you looking for? 66
66 was found 1 times.
The longest sequence is [606, 3170, 4469, 4801, 5400, 8014]
It is 6 numbers long.
Now the data shows that it's changed, the run after the data should have been changed.
elkshadow5$ ./CompileAndRun.sh
Create a new set of numbers? Y for yes. n
What number are you looking for? 1
1 was found 3 times.
The longest sequence is [1155, 1501, 4121, 5383, 6000]
It is 5 numbers long.
My code:
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;
public class jeftsdHW2 {
static Scanner input = new Scanner(System.in);
public static void main(String args[]) throws Exception {
jeftsdHW2 random = new jeftsdHW2();
int[] data;
data = new int[5000];
random.readDataFromFile(data);
random.overwriteRandNums();
}
public int countingOccurrences(int find, int[] array) {
int count = 0;
for (int i : array) {
if (i == find) {
count++;
}
}
return count;
}
public int[] longestSequence(int[] array) {
int[] sequence;
return sequence;
}
public void overwriteRandNums() throws Exception {
System.out.print("Create a new set of numbers? Y for yes.\t");
String answer = input.next();
char yesOrNo = answer.charAt(0);
if (yesOrNo == 'Y' || yesOrNo == 'y') {
writeDataToFile();
}
}
public void readDataFromFile(int[] data) throws Exception {
try {
java.io.File infile = new java.io.File("5000RandomNumbers.txt");
Scanner readFile = new Scanner(infile);
for (int i = 0; i < data.length; i++) {
data[i] = readFile.nextInt();
}
readFile.close();
} catch (FileNotFoundException e) {
System.out.println("Please make sure the file \"5000RandomNumbers.txt\" is in the correct directory before trying to run this.");
System.out.println("Thank you.");
System.exit(1);
}
}
public void writeDataToFile() throws Exception {
int j;
StringBuilder theNumbers = new StringBuilder();
try {
PrintWriter writer = new PrintWriter("5000RandomNumbers.txt", "UTF-8");
for (int i = 0; i < 5000; i++) {
if (i > 1 && i % 10 == 0) {
theNumbers.append("\n");
}
j = (int) (9999 * Math.random());
if (j < 1000) {
theNumbers.append(j + "\t\t");
} else {
theNumbers.append(j + "\t");
}
}
writer.print(theNumbers);
writer.flush();
writer.close();
} catch (IOException e) {
System.out.println("error");
}
}
}
It is possible that the file has not been physically written to the disk, using flush is not enough for this, from the java documentation here:
If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.
Because of the HDDs read and write speed, it is advisable to depend as little as possible on HDD access.
Perhaps storing the random number strings to a list when re-running and using that would be a solution. You could even write the list to disk, but this way the implementation does not depend on the time the file is being written.
EDIT
After the OP posted more of its code it became apparent that my original answer is not relatede to the problem. Nonetheless it is sound.
The code OP posted is not enough to see when is he reading the file after writing. It seems he is writing to the file after reading, which of course is what is percieved as an error. Reading after writing should produce a program that does what you want.
Id est, this:
random.readDataFromFile(data);
random.overwriteRandNums();
Will be reflected until the next execution. This:
random.overwriteRandNums();
random.readDataFromFile(data);
Will use the updated file in the current execution.
I want to make a program that each semester, creates a schedule depending of a list of classes I input, so if I add various classes, depending of the time and days that these classes will happen then the program would be able to match what classes can be added without intercepting each other. I want to know if there is an algorithms or way of comparing the class schedule in order to determine what classes can I have from the list of courses.
The only way of doing these that I can imagine is with many if statements or adding an starting course and then having an array that tracks the hours, starting each position at 0 and then each time an hour is occupied I change the array position to 1. Then when adding a course I check what positions are different to 1 and try to add the class.
I want to find a more optimal solution to this problem than the ones I can imagine.
This is a planning problem. Planning problem are very difficult to solve in a efficient way: performance issues arise very quickly in this kind of problem.
If you just want to solve the problem, you should check an existing planning problem solver like OptaPlanner: it's open source, so you can try to understand how it work and there is a blog with interresting thoughts about planning problem.
If you're wanting a method where, given a group of classes with their times and a chosen class, output the available classes, you can use simple iteration to do the job. Suppose you have a 5 hour slot with 4 classes you could represent each class with a single array:
int[][] times = {
{0,1,1,0,0},
{1,1,0,0,0},
{0,1,0,0,0},
{0,0,0,1,1}
};
So if you were to choose the class taking up the last 2hrs then the remaining options would be:
{0,1,1,0,0},
{1,1,0,0,0},
{0,1,0,0,0}
Given this representation you could do something like:
import java.util.*;
public class C {
static int[][] available(int[] c,int[][] times){
ArrayList<Integer> index = new ArrayList<>();
ArrayList<Integer> result = new ArrayList<>();
for(int i=0;i<c.length;i++)
if(c[i]==1) index.add(i);
for(int i = 0; i < times.length; i++){
if(!times[i].equals(c)) {
for (int j = 0; j < times[0].length; j++) {
if(times[i][j]==1){
if(index.contains(j)) break;
}
if(j==times[0].length-1) result.add(i);
}
}
}
int[][] r = new int[result.size()][c.length];
for(int i=0;i<result.size();i++){
r[i] = times[result.get(i)];
}
return r;
}
public static void main(String[] args) {
int[][] times = {
{0,1,1,0,0},
{1,1,0,0,0},
{0,1,0,0,0},
{0,0,0,1,1}
};
int[] c = {0,0,0,1,1};
available(c,times);
System.out.println(Arrays.deepToString(available(c,times)));
}
}
I am busy writing an algorithm that will scan a text file and add its contents into an array. However I keep getting an error message which says:
"Exception in thread "AWT-EventQueue-0"
java.util.NoSuchElementException"
I have read up on the java documents and learned that this error has something to do with the fact that I haven't set up my text file properly, however I do not understand how to fix it.
I have included my code and the contents of the text file:
String [] CardPictureNames = new String [16];
try {
Scanner car = new Scanner (new File("cardNames.txt")).useDelimiter("#");
String CN = "";
while(car.hasNext()){
for(int j=0; j <= CardPictureNames.length; j++ ){
CN = car.next();
CardPictureNames[j] = CN;
}
}
car.close();
}
catch (FileNotFoundException ex) {
Logger.getLogger(MemoryForm.class.getName()).log(Level.SEVERE, null, ex);
JOptionPane.showMessageDialog(this,"The file containing the names of the cards is missing.");
}
Here are the contents of the text file:
2 of Clubs#
10 of Clubs#
Ace of Hearts#
Ace of Spades#
Joker#
King of Hearts#
Queen of Clubs#
Queen of Diamonds#
2 of Clubs#
10 of Clubs#
Ace of Hearts#
Ace of Spades#
Joker#
King of Hearts#
Queen of Clubs#
Queen of Diamonds#
Can someone please explain to me how I can fix this problem?
Thank you in advance.
Replace your while/for loop combo with this
for(int j=0; j <= CardPictureNames.length; j++ ){
if (car.hasNext()) {
CN = car.nextLine();
CardPictureNames[j] = CN;
}
}
What you are attempting to do is loop it twice. Which is unnecessary. The if statement is added to prevent the exception from happening by not running the code that gets the card names unless there is another line (which there isn't at the end)
Now I'm assuming there is a better way to do this. But this works. And the so called "better" way probably wouldn't make much of a difference.
Im trying to write a game of Yahtzee as part of an online course (not actually enrolled, just playing along at home) I have hit a bit of a wall manipulating values in the array that keeps track of the dice values. This is the section of code that seems to be causing trouble;
for (int i=0; i<N_DICE; i++){ //goes through each die.
if (display.isDieSelected(i) == false){ //checks if player wants to reroll the die.
dice [i] = dice[i];//problem line-should reassign the same value back to the die.
}
else {
dice [i] = rgen.nextInt(1, 6);
}
}
Assigning a new random number works, and if I roll all 5 dice every turn its happy.
I've changed the offending line to dice[i]=1 for testing purposes and while it takes some fun out of the game, the program works, so I'm thinking its something simple I'm doing wrong with that line.
I've tried assigning dice[i] to a temp variable (inside and out of the if loop) and then assigning temp back to dice[i].
I've tried just leaving the if loop empty.
I've tried setting it up as a multi dimesional array with a seperate array for each roll.
I've tried adding a cast (didnt think that'd do it but I was out of ideas).
All of these have had the same results.
Only been programming a few weeks, I'd be very gratefull if someone could tell me what I'm doing wrong.
Not sure what you're trying to do with that line:
dice[i] = dice[i];
Since it's a NOP, why not just omit it?
I don't really see the purpose of:
dice[i] = dice[i]
Can't you just use something like:
for (int i=0; i<N_DICE; i++){
if (display.isDieSelected(i)){
dice [i] = rgen.nextInt(1, 6);
}
}
The code looks completely correct, although I would write it a bit more compactly:
for (int i = 0; i < N_DICE; i++) {
if (display.isDieSelected(i)) {
dice[i] = rgen.nextInt(1, 6);
}
}
So your problem probably lies somewhere else. Is dice a new array, or is it always the same in the program? If it is a field in some class, it should have the final modifier, like this:
public class YahtzeeState {
private final int[] dice = new int[N_DICE];
}
This declaration makes sure that the dice array cannot be replaced later with a completely different array. The values in the array can still be changed though.
How is the dice-array initialized? I don't know your entire code but I could imagine that it doesn't work because the dice-array gets it values only in this loop?
Maybe you should try something like:
for (int i=0; i<N_DICE; i++){
if (display.isDieSelected(i) || dice[i] == null)
dice [i] = rgen.nextInt(1, 6);
}