local scroll = 0;
local jump = 0;
local char = ">";
local coins = 0;
local x,y = term.getSize()

function newCoin(posX, posY)
	term.setCursorPos(posX - scroll, posY + jump)
	if not posX  - scroll < x then
		if(posX - scroll == x/2 and posY + jump == y-10)then
			coins = coins+1
		else
			write("O")
		end
	end
end

function redraw()
	term.clear()
	term.setCursorPos(1,1)
	write("Coins: " ..coins)
	term.setCursorPos(x/2, y-10)
	write(char)
	for i=1,x-1 do
		term.setCursorPos(i, y-9 + jump)
		write("A")
	end

	newCoin(x/2, y-14)
end

while true do
	redraw()
	local event, a, b = os.pullEvent();
	if(event == "char" and a == "a")then
		scroll = scroll-1
		char = "<"
	elseif(event == "char" and a == "d")then
		scroll = scroll+1
		char = ">"
	elseif(event == "key" and a == 57)then
		jump = 1
		for i=1,4 do
			sleep(0.1)
			jump = i
			redraw()
		end
		for i=1,4 do
			sleep(0.1)
			jump = jump-i
			redraw()
		end
		jump = 0
	end
end