View.Set ("graphics:max,max")
var x : array 1 .. 7 of int := init (0, 0, 0, 0, 0, 0, 0)
var y : array 1 .. 7 of int := init (0, 0, 0, 0, 0, 0, 0)
var mx, my, mb : int
var clickCount : int := 0

mousewhere (mx, my, mb)

for i : 1 .. upper (x)
    x (i) := my
    y (i) := mx

   end for
loop
    mousewhere (mx, my, mb)
    loop
        mousewhere (mx, my, mb)
        if mb = 1 and clickCount = 0 then
            drawfilloval (mx, my, 5, 5, blue)
            clickCount += 1
        elsif mb = 1 and clickCount >= 1 then
            drawfilloval (mx, my, 5, 5, blue)
            drawline (mx, my, x (2), y (2), red)
            clickCount += 1
        elsif mb = 1 and clickCount >= 4 then
            drawfilloval (x (7), y (7), 10, 10, white)
            drawline (x (1), y (1), x (2), y (2), white)
        end if

    end loop
 
    for decreasing i : 4 .. 2
        x (i) := x (i - 1)
        y (i) := y (i - 1)
    end for


    x (1) := mx
    y (1) := my

end loop