currentx = 0
currenty = 0
function move (n,str)
    function forward(n)
        while n > 0
            do turtle.forward()
            n = n - 1
            currenty = currenty + 1
        end
    end
    function back(n)
        while n > 0
            do turtle.back()
            n = n - 1
            currenty = currenty - 1
        end
    end
    function right(n)
        while n > 0
            do turtle.turnRight()
            turtle.forward()
            n = n - 1
            currentx = currentx + 1
            turtle.turnLeft()
        end
    end
    function left(n)
        while n > 0
            do turtle.turnLeft()
            turtle.forward()
            currentx = currentx - 1
            n = n - 1
            turtle.turnRight()

        end
    end
if str == "forward"
    then forward(n)
elseif str == "back"
    then back (n)
elseif str == "right"
    then right(n)
elseif str == "left"
    then left (n)
else
    print("string error, not a direction")
    print("or bug in function move")
end
end
function plot(desiredx,desiredy)
    local movementx = desiredx - currentx
    local movementy = desiredy - currenty
    if movementy < 0
        then movementy = -movementcurrenty
        move(movementy,"back")
    else
        move(movementy,"forward")
    end
    if movementx < 0
        then movementx = -movementcurrentx
        move(movementx,"left")
    else
        move(movementx,"right")

    end

    turtle.placeDown()


end

function drawcircle (radius)
    turtle.up()
    turtle.placeDown()
    local f = 1 - radius
    local ddx = 0
    local ddy = -2*radius
    local x = 0
    local y = radius
    plot(0,0 + radius)
    plot(0, 0 - radius)
    plot(0 + radius,0)
    plot(0 - radius,0)
    while x < y
        do
        if f >= 0
            then y = y - 1
            ddy = ddy + 2
            f = f + ddy
        end
        x = x + 1
        ddx = ddx + 2
        f = f + ddx + 1
        plot (0 + x,0 + y)
        plot (0 - x, 0 + y)
        plot (0 + x, 0 - y)
        plot (0 - x, 0 - y)
        plot (0 + y, 0 + x)
        plot (0 - y, 0 + x)
        plot (0 + y, 0 - x)
        plot (0 - y, 0 - x)
    end
end

function reset ()
    currentx = 0
    currenty = 0
end
print("Good day, radius please")
radius = tonumber(read())
drawcircle(radius)