I am trying to find all the solutions and put them together at a single place, So feel free to add comments and if you have a solution please do post. Cheers … 🙂
Here is the puzzles link : http://www.wuriddles.com/
The master of a college and his wife has decided to throw a party and invited N guest and their spouses. On the night of the party, all guests turned up with their spouse, and they all had a great time. When the party was concluding, the master requested all his guests (including his wife, but not himself) to write down the number of persons they shook hands with, and to put the numbers in a box. When the box was opened, he was surprised to find all integers from 0 to 2N inclusive.
Assuming that a person never shake hands with their own spouse and that no one lied, how many hands did the master shake?