Can't figure out the structure of code for Lab 2 Level 5 about 2122-s2

[jingyulim1]

For move, you need to track where the "." is. You can do this by using a number (since the grid only hold interger) that you won't use in the puzzle the hold the "." in the grid. Then, proceed to check if that number is either in same row, different column by 1 or different row by 1, same column with the input number(Math.abs can be helpful). If so, then set a new grid and return a new Puzzle, else return this.

For isSolved, remember that creating a new Puzzle returns a solved Puzzle. So you can just compare the toString().

Hope this helps.

[GraceYongXM]

To add on, when checking whether the number is beside the ".", do take note of special cases which will cause the indexOutOfBound error!

[calvinseptyanto]

Hi,

I think one of the easiest way is to make another constructor that has additional currentBlankPosition parameter. In that way you can easily check whether the 1D pos translation of the number that you want to swap to the currentBlankPosition (in 1D translation ozo)

*Also can interpret "." as 0 in your ImList, and do filter the 0 when you print it out

[undeser]

Hi,

What worked for me was adding 0 into Grid2D, since it can only take in Integer inputs, to replace the ".". Also, a way to identify the position of the 0, both row and column positions.

Afterwards, checking if num from Puzzle move(int num) is
(1) same row as 0 or;
(2) same column as 0 but are on top of one another

Lastly, it is to edit the Grid2D using the .set() function and return a new Puzzle which is initialised using this edited Grid2D.