Question 65
Antoine suggests to Baptiste that they play "crazy alphabet": they start by agreeing on a letter. Then, taking turns, each of them may choose to say between 1 and 2 of the following letters of the alphabet, starting from $A$. Whoever says the chosen letter wins. If Antoine starts, for which starting letters does he have a strategy that guarantees him a win?
Here is an example of a game: the letter chosen initially is $E$. Antoine says "A", Baptiste "BC", Antoine "CD" and Baptiste says "E". In this case, Baptiste has won.
Here is an example of a game: the letter chosen initially is $E$. Antoine says "A", Baptiste "BC", Antoine "CD" and Baptiste says "E". In this case, Baptiste has won.