Problem 7.3. Lёsha gathered friends to play hide and seek. He surveyed Andrey, Borya, Vasya, Gena, and Denis and found out the following.

- If Andrey goes to play hide and seek, then Borya will go too, but Vasya will not.
- If Borya goes to play hide and seek, then Gena or Denis will also go.
- If Vasya does not go to play hide and seek, then Borya and Denis will not go either.
- If Andrey does not go to play hide and seek, then Borya will go, but Gena will not.

In the end, Lёsha played hide and seek with someone. With whom exactly? (All the boys stuck to their opinions.)
Answer: With Borya, Vasya, and Denis.

Solution. Regardless of whether Andrey goes to play hide and seek, Borya will definitely go. Then Vasya will also go to play hide and seek (if Vasya didn't go, then Borya wouldn't go either). Then Andrey will not go to play hide and seek (if Andrey went, then Vasya wouldn't go). Then Gena will definitely not go. Since Borya will go, either Gena or Denis will also go. Since Gena will not go, then Denis will go. Therefore, only Borya, Vasya, and Denis played hide and seek with Lesha.