Two players and take alternate turns in a game, starting with the diagram alongside. At each turn, one player writes one of 1, 2 or 3 in an empty circle, so that no two circles connected by an edge contain the same number. A player loses when they cannot go. In each of the five diagrams below it is ’s turn. In which of the diagrams can ’s move ensure that loses the game?
Select one option, then click Submit.
A
B
C
D
E
Select an option, then submit.
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Junior Mathematical Challenge (2019)
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