Practice problem
Relations in Math - Definition & Examples
===

Image Source: By Expii Solve
Numerous celebrities have announced that they’re thinking about running for president in 2020. Each candidate for president has a list of preferences for vice president; similarly, each candidate for vice president has a list of preferences for president.
A stable candidacy is one where any two presidents wouldn’t try to swap vice presidents. For example, if President A is matched with Vice President A and President B is matched with Vice President B, but President A prefers Vice President B and President B prefers Vice President A, this is not a stable candidacy.
Here are the candidates for the two positions and their preferences:

Select the set of stable candidacies.