Greenfoot

2021/10/13

#

I am having problems with comparing elements of an Integer ArrayList (single dimension) with certain values. Is there anyone who sees what I'm doing wrong? Here I declare the new lists:

 private List listx1 = new ArrayList<Integer>();
    private List listy1 = new ArrayList<Integer>();
    private List listx2 = new ArrayList<Integer>();
    private List listy2 = new ArrayList<Integer>();

Here I add numbers to them:

        else if(Greenfoot.isKeyDown("enter") && canPlace() && !menuTime)
        {
            int e = getX();
            int f = getY();
            if(player==1)
            {
                getWorld().addObject(new cross(),e,f);
                setImage("naught-small.png");
                listx1.add(e);
                listy1.add(f);
                if(doesWin(listx1) || doesWin(listy1) || diagonalWin(listx1, listy1))
                    System.out.print("Hooray! Crosses wins!\n");
                wait(20);
                player = 2;
            }
            else
            {
                getWorld().addObject(new naught(),e,f);
                setImage("cross-small.png");
                listx2.add(e);
                listy2.add(f);
                if(doesWin(listx2) || doesWin(listy2) || diagonalWin(listx2, listy2))
                    System.out.print("Hooray! Naughts wins!\n");
                wait(20);
                player = 1;
            }
        }

Here I check (very inefficiently probably) if there are 3 of the same items in the list:

    public boolean doesWin(List x)
    {
        Collections.sort(x);
        if(Collections.frequency(x, 100) == 3 || Collections.frequency(x, 300) ==3 || Collections.frequency(x, 500) == 3)
            return true;
        else
            return false;
    }

And here I check for a diagonal win, so that would mean I have a same x and y, with 3 different values. In the contains method it goes wrong at the line "int placeholder = x.get(i);" I get the error "incompatible types: jave.lang.Object cannot be converted to in".

    public boolean diagonalWin(List x, List y)
    {
        if(contains(x, 100) && contains(y,100))
            return true;
        return false;
    }
    
    public boolean contains(List x, int z)
    {
        for(int i=0; i<x.size(); i++)
        {
          int placeholder = x.get(i);
        }
        return false;
    }

Every bit of help is welcome, as I searched the web for over an hour for a solution already but I can't find it.

danpost

2021/10/13

#

Very inefficient. Use a 3 by 3 int array to represent the grid, 0 representing an empty square, and 1 and -1 representing the crosses and naughts. The 1s and -1s can come from a turn field representing whose turn it is. It would be quite easy to check for a win with the array set up this way.

Windeycastle

2021/10/14

#

Yes, but how do you take those items out of the list to compare them?

danpost

2021/10/14

#

Windeycastle wrote...

Yes, but how do you take those items out of the list to compare them?

// global declarations
int[][] grid = new grid[3][3]; // grid array
int turn = 1; // player at turn (1 for crosses; -1 for naughts)

// in act of world
if (numberOfObjects() < 9 && Greenfoot.mouseClicked(this))
{
    MouseInfo mi = Greenfoot.getMouseInfo();
    int x = mi.getX(), y = mi.getY();
    if (grid[y][x] != 0) return; // do nothing if grid square occupied
    grid[y][x] = turn; // make entry
    addObject((turn == 1 ? new Cross() : new Naught()), 100+200*x, 100+200*y);
    if (doesWin(x, y)) gameOver(turn);
    else if (numberOfObjects() == 9) gameOver(0);
    turn = -turn;
}

// to tell is current turn wins
private boolean doesWin(int x, int y)
{
    int n = grid[y][x];
    if (n == grid[y][(x+1)%3] && n == grid[y][(x+2)%3]) return true; // row check
    if (n == grid[(y+1)%3][x] && n == grid[(y+2)%3][x]) return true; // column check
    if (x == y && n == grid[(y+1)%3][(x+1)%3] && n == grid[(y+2)%3][(x+2)%3]) return true; // back-slash diagonal check
    if (x+y == 2 && n == grid[(y+1)%3][(x+2)%3] && n == grid[(y+2)%3][(x+1)%3]) return true // forward-slash diagonal check
    return false; // no win found
}

// game over routine
private void gameOver(int winner)
{
    String txt = null;
    switch (winner)
    {
        case 1 : txt = "Crosses\nwins"; break;
        case -1 : txt = "Naughts\nwins"; break;
        case 0 : txt = "Draw\ngame"; break;
    }
    GreenfootImage img = new GreenfootImage(txt, 60, new Color(0, 0, 0, 128), new Color(0, 0, 0, 0));
    getBackground().drawImage(img, 300-img.getWidth()/2, 300-img.getHeight()/2);
}

Windeycastle

2021/10/15

#

This is the answer I've been looking for!! Thank you sl much, I will use all of your ideas here but ttry to implement them a bit different so it is still something I made and not your copy, but I'll set you definitly in the documentation =)

danpost

2021/10/15

#

I found an inconsistency in my code. If world size is (600, 600, 1), line 9 should have x and y divided by 200. If world size is (3, 3, 200), line 12 should use just x and y.

Windeycastle

2021/10/15

#

I did a complete rarrangement and changed the rediculous world size of 600,600,1 to 1,1,200. Makes a lot of code easier and more understandable.

danpost

2021/10/15

#

Windeycastle wrote...

I did a complete rarrangement and changed the rediculous world size of 600,600,1 to 1,1,200. Makes a lot of code easier and more understandable.

You do mean (3, 3, 200), don't you?

Windeycastle

2021/10/15

#

Yes (insert facepalm)

Windeycastle

2021/10/15

#

Hmm, working on the program now, but it gives an error when declaring the array? It says "unknown type: grid" at the right side of the "=".

Super_Hippo

2021/10/15

#

I think it should be

int[][] grid = new int[3][3];

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Pulling items out of lists troubles