The challenge is over, the winner is Hive account@kouba01 You can still read this wonderful puzzle.

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Josef and Roi became friends of Sarit and they want to know when her birthday. Sarit presents them with a list of twelve possible dates:

January 14, January 15, January 18, February 16, February 17, February 13, February 15

March 13, March 15,

December 13, December 14 and December 16.

Sarit reveals to Josef and Roi, respectively, to each the month and to the other the day she was born.

(We do not know which of them she told what day\month.)

Josef: I do not know when Sarit's birthday is, but I know Ro'i does not know either.

Roi: At first I did not know when Sarit's birthday was, but now I know.

Josef: So I know when her birthday is as well.

So - when was Sarit's birthday?

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