One common starting configuration is a straight bar with alternating upper and lower prisms, with the rectangular faces facing up and down, and the triangular faces facing towards the player. The 12 lower prisms are numbered 1 through 12 starting from the left, with the left and the right sloping faces of these prisms are labeled L and R respectively. The last of the upper prisms is on the right, so the L face of prism 1 does not have an adjacent prism.