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Puzzle 73: Does Private Perkins end up facing the right way on parade?

19 August 2020

#73 Changing guard

Fifteen members of the King’s 99th Dragoons are standing on parade. “Right turn!” screams the sergeant, and each soldier makes a 90° turn. Unfortunately, many of the squad struggle to know their left from their right. After this manoeuvre, five soldiers end up facing left, including Private Perkins, who is in the middle of the row.

X X X X X X X P X X X X X X X

Any soldier that ends up face to face with another soldier now does a 180° turn. This awkward ritual continues until no soldier can see…

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