#import "@preview/fletcher:0.6.0" as fletcher: diagram, edge, node

#import fletcher.cetz.draw: group, set-style

#diagram(
node-stroke: 0.8pt,
node-radius: 2.5pt,
node-fill: yellow,
spacing: (20pt, 10pt),
{
for y in range(6) {
node((0, y))
node((-0.5, y), $q^#y$, stroke: none, fill: none)
}

edge((0, 0), auto, corner: "-|")
edge((0, 1), auto, "--", corner: "-|")
node((1, 0.5), <a>)

edge((0, 2), auto, corner: "-|")
edge((0, 3), auto, corner: "-|", $ * $, center)
edge((0, 4), auto, corner: "-|")
node((1, 3), <b>)

edge(<a>, auto, "--", corner: "-|")
edge(<b>, auto, corner: "-|")
node((2, 1.75), <c>)

edge((0, 5), "rrr,uu")
edge(<c>, (3, 3), "--", corner: "-|")
node((3, 3))
edge("--|>")

node((4, 3), $Q^*$, shape: rect, fill: none)
},
)