This enigma was sent to me by Thomas Roux. I hurried to submit it to the students of the ENSI of Caen through the medium of the school's newspaper. Now it is up to you!
Thirteen couples meet in a party. Each guest kisses or shakes hands with each member of the other couples, independently of its sex. In the evening, a man asks all the other guests, including his wife, how many hands they have shaken. Knowing he obtained answers all different, find how many himself and his wife have shaken hands.