algorithm pseudocode cheat sheet

RECURSIVE BACKTRACKING ALGORITHM PSEUDOCODE

*CODE STRUCTURE*

create stack
create list for pathed tiles
pick start tile
add start tile to list
add start tile to stack
assign start tile to cur_tile
WHILE stack is not empty{
	IF cur_tile has neighbor unpathed
	{
		connect and move to random neighbor
	}
	ELSE IF cur_tile has no neihbors unpathed
	{
		pop from path and assign poped to cur_tile
	}
}


A* PATHFINDING ALGORITHIM PSEUDOCODE

*TERMS*

h-score - the heuristic cost of a tile, or how far it is from the end_tile
g-score - the gained cost of a tile, or how much was spent to get to it.
m-score - the move score, or the h-score + g-score

*CODE STRUCTURE*

*CREATE EVENT CODE*

create a grid of pathing nodes.
create a list of neighbors for each node containing the surrounding nodes of each node
create a parent variable for each node and set them to null
create a child variable for each node and set to null

*FUNCTION TO ACTUALLY PATHFIND*

next_node_in_path pathfinding_function(start_node,end_node)
{
	create OPEN priority list
	create CLOSED list
	cur_node = start_node
	add cur_node to CLOSED
	WHILE cur_node != end_node
	{
		FOR each neighbor of current node
		{
			IF neighbor is traversible (not a wall) and not in CLOSED
			{
				IF neighbor is not in OPEN
				{
					h-score of neighbor
					get g-score of neighbor
					get m-score of neighbor
					add neighbor to OPEN with priority of m-score
				}
				ELSE IF new g-score to neighbor is smaller than previous g-score path
				{
					calculate new g-score
					get m-score of neighbor
					add neighbor to OPEN with a priority of m-score
				}
			}
		}
		IF open is empty (no paths left!)
		{
			delete datastructures CLOSED and OPEN to avoid memory leaks!
			return NULL
		}
		else
		{
			new_node = ds_priority_delete_min(OPEN);
			new_node.parent = cur_node
			new_node = cur_node
			add cur_node to CLOSED
		}
	}
	WHILE cur_node != start_node
	{
		cur_node.parent.child = cur_node;
		cur_node = cur_node.parent;
	}
	delete datastructures CLOSED and OPEN to avoid memory leaks!
	return cur_node.child
}