For those who don't have excel or can't download the file for any reason here's the riddle:
8 people need to cross a river: a father, a mother, 2 sons, 2 daughter, a policeman and a criminal.
The rules are:
1. The float can allow maximum two people
2. The father cannot stay with any of the daughters without the mother's presence
3. The mother cannot stay with any of the sons without the father's presence
4. The prisoner cannot stay alone with any family member
5. Only policeman and the parents can sail the float through river