radius =tonumber(read())
x = -1
y = 0

function round(x)
 n = x % 1

 if n >= 0.5 then
  return math.ceil(x)
 else
  return math.floor(x)
 end
end

function getQuaterSector(r)
 sectorEdges = {}

  while x < r^2 do
   x = x + 1
   y =math.sqrt(r^2 - x)

   if math.sqrt(x) % 1 == 0 then
    table.insert(sectorEdges,{math.sqrt(x),round(y)})
   end

  end

 return sectorEdges
end

function moveToOnYPlane(x1,z1,x2,z2)

 XDiff=x2-x1
 if XDiff>0 then
  turtle.turnRight()
 elseif XDiff<0 then
  turtle.turnLeft()
 end

 if XDiff<0 then XDiff = -XDiff end
  i=0

  while i<XDiff do
   turtle.placeDown()
   turtle.forward()
   i=i+1
  end

 if XDiff>0 then
  turtle.turnLeft()
 elseif XDiff<0 then
  turtle.turnRight()
 end

 ZDiff =z2-z1
 if ZDiff<0 then
  turtle.turnLeft()
  turtle.turnLeft()
 end

 if ZDiff <0 then ZDiff = -ZDiff end

 b=0
 while b<math.abs(ZDiff) do
  turtle.placeDown()
  turtle.forward()
  b = b+1
 end

 if ZDiff<0 then
  turtle.turnLeft()
  turtle.turnLeft()
 end

end

--[[
This next block isn't working
>get this to take the array and
>print the quarter sector, placing below
>then turn and repeat *3 times
>move up a layer and reduce radius
>repeat process and bam a sphere
--]]

arr = getQuaterSector(radius)

a=1
currentX=0
currentZ=0
moveToOnYPlane(0,0,currentX,currentZ)
while a < table.getn(arr) do
 moveToOnYPlane(currentX,currentZ,arr[a][1],arr[a][2])
--  currentX=arr[a][1]
--  currentZ=arr[a][2]
moveToOnYPlane(currentX,currentZ,0,0)
 a = a + 1
end