io.input("test")
io.input("input")


function pos2index( pos )
  return pos.x*10000 + pos.y
end

function constrain( n, min, max )
  local min = min or -1
  local max = max or 1
  if n < min then return min
  elseif n > max then return max
  else return n
  end
end


local head = { x=1, y=1 }
local tail = { x=1, y=1 }
local visited = { [pos2index(tail)] = true }

for line in io.lines() do
  local dir, q = string.match(line, "^(%a) (%d+)$")
  q = tonumber(q)
  for step = 1,q do
    if dir == "R" then
      head.x = head.x + 1
    elseif dir == "L" then
      head.x = head.x - 1
    elseif dir == "U" then
      head.y = head.y + 1
    elseif dir == "D" then
      head.y = head.y - 1
    end

    local dif = { x=head.x-tail.x, y=head.y-tail.y }
    if dif.x == 0 and math.abs(dif.y) > 1 then
      tail.y = tail.y + constrain(dif.y)
    elseif dif.y == 0 and math.abs(dif.x) > 1 then
      tail.x = tail.x + constrain(dif.x)
    elseif math.abs(dif.x)>1 or math.abs(dif.y)>1 then
      tail.y = tail.y + constrain(dif.y)
      tail.x = tail.x + constrain(dif.x)
    end
    print( tail.x, tail.y, head.x, head.y, dif.x, dif.y)
    visited[ pos2index(tail) ] = true
  end
end

local result = 0
for k, v in pairs(visited) do
  print(k)
  result = result + 1
end
print("part 1", result)