Really long post about multidemensional arrays

[Alex Ba]

public int candidates;
public String[] names;
public int[][] ballot;
public int voters;
public void setNames(int i)
{
    candidates = i;
    names = new String[candidates];
    Scanner kb = new Scanner(System.in);
    int n = 0;

    String name;
    while(n < candidates)
    {
        System.out.println("Enter a candidate");
        name = kb.nextLine();
        names[n] = name;
        n++;
    }
}

public void printNames()
{
    int n = 0;
    System.out.println("The candidates are:");
    while (n < candidates)
    {
        System.out.print(names[n] + " ");
        n++;
    }
}

public void vote()
{
    System.out.println("\nPlease enter your vote");
    System.out.println("Please enter votes: 1,2,3,4,5 etc");
    Scanner kb = new Scanner(System.in);

  //  int k = voters * candidates;

    ballot = new int[voters][candidates];

    int first = 0, second = 0;
    String voteString;

    //int n = voters * candidates;
    while(first < voters)
    {
        while(second < candidates)
        {
            voteString = kb.nextLine();
            int count = voteString.length() - 1;
            int track = 0;

            while(track < count - 2)
            {
                char c = voteString.charAt(track);
                int k = Integer.parseInt(Character.toString(c));
                ballot[first][second] = k;
                track = track + 2;
            }
            second++;
        }
        second = 0;
        first++;
    }
}
public void printVotes()
{
    int first = 0, second = 0;

    while(first < voters)
    {
        while(second < candidates)
        {
            System.out.println(ballot[first][second]);
            second++;
        }
        second = 0;
        first++;
    }
}

If you enter 2 candidates and 3 voters, instead of entering votes 3 times, you enter them 6 and I can't see why. Also, for the printVotes method, it just prints 0s. Anyone see any huge holes in my logic? I can't figure out for the life of me why it's not working.

[Alex Ba]

I should add the main class:

    public static void main(String[] args) {
        // TODO code application logic here

        election election1 = new election();

        System.out.println("Please enter the number of candidates");
        Scanner kb = new Scanner(System.in);
        int i = kb.nextInt();
        election1.setNames(i);
        System.out.println("Please enter the number of voters");
        election1.voters  = kb.nextInt();
        election1.printNames();
        election1.vote();
        election1.printVotes();

    }

[Patricia Samuel]

Hi Alex,

Please let me know what input this line takes for the test case you have provided -

# System.out.println("\nPlease enter your vote");
# System.out.println("Please enter votes: 1,2,3,4,5 etc");
# Scanner kb = new Scanner(System.in);

Thanks
Patricia

[Campbell Ritchie]

That wasn't a long post.

What's a multidimensional array? Java doesn't support them. It supports arrays of arrays.

And for your logic, you will have to get a pencil and paper and go through the control flow in your program until you find why you are asking six times. Hint 3 × 2 = 6

[Alex Ba]

Patricia Samuel wrote:Hi Alex,

Please let me know what input this line takes for the test case you have provided -

# System.out.println("\nPlease enter your vote");
# System.out.println("Please enter votes: 1,2,3,4,5 etc");
# Scanner kb = new Scanner(System.in);

Thanks
Patricia

That input is in the while loop

voteString = kb.nextLine(); 

The input would be something like 1,2 or 2,1 aka, which person is your number 1 preference, and which is your number 2. From there, that string is getting split up into individual characters and entered into various slots in the array. It's not doing that.

[Alex Ba]

Hey I figured it out.

while(first < voters)
    {
            voteString = kb.nextLine();
            track = 0;
            while(track < voteString.length())
            {
                char c = voteString.charAt(track);
                ballot[first][second] = Integer.parseInt(Character.toString(c));
                track = track + 2;
                second++;
            }
        second = 0;
        first++;
    }
}

is the current while loop. It seems to be working.

[Patricia Samuel]

Great

I was just going to get my pencil and paper

[Alex Ba]

Seems as though doing things on paper first makes programming easier.
Wish my professor would've mentioned that

[Campbell Ritchie]

I only go to one module now, and sit at the back and help the undergraduates. I seem to spend half my time telling them to get a small pencil . . .






























. . . and a large eraser