Step 1
The first 16 coins |
When the first 16 coins are placed,
your topspin will look like this:
No particular algorithm |
Step 2
The 17th coin
Coin 17 must first be placed in position 3 or 4
If coin 17 is in position 4, everything is fine, otherwise there is one possible scenario: |
When the 17th coin is placed,
your topspin will look like this:
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Case where coin 17 is in position 3
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Step 3
The 18th coin
You must first place coin 17 in position 4
If coin 18 is in position 3, everything is fine, otherwise there are 2 possibilities: |
When the 18th coin is placed,
your topspin will look like this:
|
Case where coin 18 is in position 2
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Case where coin 18 is in position 1
the coin is then in position 2, so you must perform the algorithm opposite
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Step 4
The 19th and 20th pieces
First, piece 17 must be placed in position 4
If piece 19 is in position 2, everything is fine; otherwise, there are two possibilities: |
When the 19th and 20th pieces are placed,
your topspin will look like this:
|
Case where piece 19 is in position 1
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