Thread: Tile puzzle game getting tiles to move (help)

I am building a class called TilePuzzle and it is a text base game and it looks like this.

1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 #

The way I programmed the move method it looks for the empty space(#), after finding the empty space it looks at the legal moves and compares the numbers around it to see if it is the number you passed to it, if so then switch them.

 
    public void move(int tileNumber) {
        if (!isValid(tileNumber)) {
            return;
        }
 
        for (int r = 0; r < boardSize; r++) {
            for (int c = 0; c < boardSize; c++) {
 
                if (tile[r][c] == EMPTY) {
 
                    if (r != 0 && tile[r - 1][c] == tileNumber) { // checks up position
                        tile[r][c] = tile[r - 1][c];
                        tile[r - 1][c] = EMPTY;
                    } else if (r != (boardSize - 1) && tile[r + 1][c] == tileNumber) { // checks down position
                        tile[r][c] = tile[r + 1][c];
                        tile[r + 1][c] = EMPTY;
                    } else if (c != 0 && tile[r][c - 1] == tileNumber) { // checks left position 
                        tile[r][c] = tile[r][c - 1];
                        tile[r][c - 1] = EMPTY;
                    } else if (c != (boardSize - 1) && tile[r][c + 1] == tileNumber) { // checks right position
                        tile[r][c] = tile[r][c + 1];
                        tile[r][c + 1] = EMPTY;
                    }
                }
            }
        }
    }

boardSize is equal to 4 and EMPTY is equal to #.

now the problem, so the if statements that check for up and left work but the if statements that check for down and right don't work and I tried a couple different things like put a System.out.println(); in both body of the if statement and they are excusing when call but they don't switch the numbers. I also changed the (boardSize - 1) to 3 thinking that might have something to do with it but it still didn't work.

any help or ideas would be greatly appreciated.

Here an example

you enter in 12 and the move method will switch the 12 with the empty space like so.

1 2 3 4
5 6 7 8
9 10 11 #
13 14 15 12

but if you enter 12 again it i will not switch, it just doesn't do anything. that is why I put System.out.println("test"); in the body of the down and right to see if they were being executed and they were but they don't switch the number with the empty space.

    public void move(int tileNumber) {
        if (!isValid(tileNumber)) {
            return;
        }
 
        for (int r = 0; r < boardSize; r++) {
            for (int c = 0; c < boardSize; c++) {
 
                if (tile[r][c] == EMPTY) {
 
                    if (r != 0 && tile[r - 1][c] == tileNumber) { // checks up position
                        tile[r][c] = tile[r - 1][c];
                        tile[r - 1][c] = EMPTY;
                    } else if (r != (boardSize - 1) && tile[r + 1][c] == tileNumber) { // checks down position
                        System.out.println("value of tile[r][c]: " + tile[r][c] + " value of tile[r+1][c]" + tile[r+1][c]);
                        tile[r][c] = tile[r + 1][c];
                        System.out.println("value of tile[r][c]: " + tile[r][c] + " value of tile[r+1][c]" + tile[r+1][c]);
                        tile[r + 1][c] = EMPTY;
                        System.out.println("value of tile[r][c]: " + tile[r][c] + " value of tile[r+1][c]" + tile[r+1][c]);
                    } else if (c != 0 && tile[r][c - 1] == tileNumber) { // checks left position 
                        tile[r][c] = tile[r][c - 1];
                        tile[r][c - 1] = EMPTY;
                    } else if (c != (boardSize - 1) && tile[r][c + 1] == tileNumber) { // checks right position
                        tile[r][c] = tile[r][c + 1];
                        tile[r][c + 1] = EMPTY;
                    }
                }
            }
        }
    }

run:
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 #

Enter a number: 12
1 2 3 4
5 6 7 8
9 10 11 #
13 14 15 12
Enter a number: 12
value of tile[r][c]: 35 value of tile[r+1][c]12
value of tile[r][c]: 12 value of tile[r+1][c]12
value of tile[r][c]: 12 value of tile[r+1][c]35
1 2 3 4
5 6 7 8
9 10 11 #
13 14 15 12

The value are right and it looks like they have switch but when it doesn't move.

I think i do,
but what i posted before does what you have asked I believe.

1 2 3 4
5 6 7 8
9 10 11 #
13 14 15 12
Enter a number: 12

The user enter the number 12. so the if statement should switch the # and the 12 and the board should look like this.....

1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 #

but it doesn't so i put some System.out statements in the if statement that move the number down.

//the number 35 is the empty slot.

// found the empty tile and the one above that the tile number the user enter (12)
value of tile[r][c]: 35 value of tile[r+1][c]12
// next I assign the empty tile to the value of the tile above it like so.
value of tile[r][c]: 12 value of tile[r+1][c]12
// now i set the tile that was above to empty
value of tile[r][c]: 12 value of tile[r+1][c]35

so logically everything seem to be working under the hood but its not switching them visually. It can't be the toString method because the it works when you switch is up or if the switch is left.

--- Update ---

Sorry as soon as I posted this my buddy sitting next to me suggested something and it works also figured out why my way didn't work.

thank you for your time i really appreciated.