#There you go, a ridiculously complicated solution to euler 220
#define the function that gives the instructions outputs an array
def d(n)
if n==0
["F","a"]
else
newarray(d(n-1))
end
end
#gimme a helper function that does the transformation for each iteration
#of the instructions outputs an array
def newarray(array)
$output=[]
array.each do |piece|
if piece=="a"
$output<<["a","R","b","F","R"]
else
if piece=="b"
$output<<["L","F","a","L","b"]
else
$output<<piece
end
end
end
$output.flatten
end
#define what the new direction is after an instruction L - Left
#or R - Right is given at a current direction. outputs direction
def direction(s,current_direction)
case current_direction
when :up
if s=="R"
:right
else
:left
end
when :right
if s=="R"
:down
else
:up
end
when :down
if s=="R"
:left
else
:right
end
when :left
if s=="R"
:up
else
:down
end
end
end
# define what happens to the coördinates [x,y] when a step is taken
# in a certain direction... outputs coördinates
def step(direction)
case direction
when :up
$coord[1]=$coord[1]+1
when :right
$coord[0]=$coord[0]+1
when :down
$coord[1]=$coord[1]-1
when :left
$coord[0]=$coord[0]-1
end
end
#decide a starting point at [x,y] coördinates
$coord=[0,0]
#give the starting direction
$current_direction=:up
def dragon(n,top_step)
instructions=d(n)
step=0
instructions.each do |instruction|
case instruction
when "R"
$current_direction=direction(instruction,$current_direction)
when "L"
$current_direction=direction(instruction,$current_direction)
when "F"
step+=1
step($current_direction)
if step==top_step
puts "["+$coord[0].to_s+","+$coord[1].to_s+"]"+"it da shit"
end
else
$current_direction=$current_direction
end
end
end
dragon(50, 10**12)