80 lines
1.7 KiB
Typst
80 lines
1.7 KiB
Typst
#import "@local/handout:0.1.0": *
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#import "@preview/cetz:0.4.2"
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#show: handout.with(
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title: [Warm-Up: What's an AST?],
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by: "Mark",
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subtitle: "Based on a true story.",
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)
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#problem()
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Say we have a painting on a string. \
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Hang the painting on two nails so that if either is removed, the painting falls. \
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#v(2mm)
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You may detach the string as you hang the painting, but it must be re-attached once you're done. \
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#hint[The solution to this problem isn't a "think outside the box" trick, it's a clever wrapping of the string.]
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#v(2mm)
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#align(center, cetz.canvas({
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import cetz.draw: *
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let s = 2.5
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line(
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(0 * s, 1 * s),
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(2 * s, 1 * s),
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(2 * s, 0 * s),
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(0 * s, 0 * s),
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close: true,
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stroke: (thickness: 0.8mm),
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)
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line(
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(0.1 * s, 1 * s),
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(0.5 * s, 1.5 * s),
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(1.5 * s, 1.5 * s),
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(1.9 * s, 1 * s),
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stroke: (thickness: 0.5mm, dash: "dotted"),
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)
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circle((0.5 * s, 1.5 * s), radius: 0.04 * s, fill: black, stroke: none)
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circle((1.5 * s, 1.5 * s), radius: 0.04 * s, fill: black, stroke: none)
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line(
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(0.66 * s, 0.66 * s),
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(0.66 * s, 0.35 * s),
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(0.60 * s, 0.1 * s),
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)
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line(
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(0.72 * s, 0.1 * s),
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(0.66 * s, 0.35 * s),
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)
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line(
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(0.66 * s, 0.575 * s),
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(0.6 * s, 0.475 * s),
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(0.525 * s, 0.575 * s),
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)
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line(
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(0.66 * s, 0.575 * s),
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(0.72 * s, 0.475 * s),
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(0.795 * s, 0.575 * s),
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)
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circle((0.66 * s, 0.66 * s), radius: 0.07 * s, fill: white)
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}))
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#solution([
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Say we have a left nail and a right nail. The path of the string is as follows:
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- Start on the left
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- Move over both nails, wrap right nail cw
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- Wrap left nail ccw
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- Wrap right nail ccw
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- Exit downwards, in between both nails
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])
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