added disk scheduling diagrams

disk-scheduling/utils.typ

@@ -0,0 +1,58 @@
+#import "@preview/cetz:0.3.1": canvas, draw
+
+#let draw-algo(places, min: 0, max: 199, width: 10) = canvas({
+  let m = min
+  let M = max
+  let s = M - m
+  let w = width / s
+
+  draw.line((0, 0), (width, 0))
+  let draw-tick(v) = {
+    draw.line((v*w, 0), (v*w, 0.2))
+    draw.content(
+      (v*w, 0.2),
+      str(v),
+      anchor: "south",
+      padding: 3pt
+    )
+  }
+
+  let drawn = (m, M)
+  draw-tick(m)
+  draw-tick(M)
+
+  let pos = ()
+  for (i, place) in places.enumerate() {
+    if place not in drawn {
+      draw-tick(place)
+      drawn.push(place)
+    }
+    
+    let p = (place * w, -i * 0.5)
+    if pos.len() != 0 {
+      draw.line(pos.last(), p, mark: (end: "straight"))
+    }
+    pos.push(p)
+  }
+
+  let bottom-y = -(places.len() - 1) * 0.5
+  draw.line((m*w, 0), (m*w, bottom-y))
+  draw.line((M*w, 0), (M*w, bottom-y))
+})
+
+#let compute-total(places, wrap: false, min: 0, max: 199) = {
+  let total = 0
+  for i in range(places.len() - 1) {
+    let p0 = places.at(i)
+    let p1 = places.at(i + 1)
+    let d = calc.abs(p0 - p1)
+    if wrap {
+      if p1 < p0 {
+        d = (max - p0) + (p1 - min)
+        // d = 0
+      }
+    }
+    total += d
+  }
+  return total
+}