1.3 KiB
Now, after two pseudo-pathfinding problems we finally get a real one.
The right solution would proably be to search online for dijkstras algorithm, but I'm lazy and I kinda remember the essence - so I implement my own algorithm from what I remember about pathfinding :D.
The general idea is still the same - we generate a 80x80 grid where each cell contains the minimal distance to the node [0,0].
At the end we just have to look at the value of distance[79, 79].
Initially all distances are set to an absurdly high number.
Additionally we have a a 80x80 marker-grid where we mark cells either UNKNOWN (#), MARKED (0) or FINISHED (1).
Initially all cells are Unknown.
We start our algorithm by setting distance[0, 0] = data[0, 0] and marker[0, 0] = MARKED
Then we execute the main loop until all cells are marked with FINISHED, in our main loop we do:
- Search fo a MARKED cell
- Calculate for all 4 directions the distance:
distance = distance[x, y] + data[x+1, y](orx-1,y+1,y-1, depending on the direction)- If the calculated distance is less than the cached value (
distance[x+1, y]) update the distance and set the updated cell to MARKED - Set our current cell to FINISHED (
marker[x, y] = FINISHED)
Rinse and repeat until finished.