# t09 in C4B figure 8

def f():
    var i, j, x, r
    i = 1
    j = 0
    while j < x:
    	j = j + 1
        if i >= 10:
        	i = 1
        	tick 40
        else:
        	r = unif(1,3)
        	i = i + r

        tick 1