tranlate to korean ;A programmer may be asked to write an algorithm to solve the problem of determining if a set of K people who all know each other exists within a graph of a social network?

For the example social network graph and K $=3,$ the algorithm should return yes. Xiao, Sean, and Tanya all know each other. Sean, Tanya, and Eve also all know each other.

For K $=4,$ no set of $4$ individual who all know each other exists, and the algorithm, should return no$.$

This problem is equivalent to the clique decision problem, which is NP$-$complete, and no known polynomial time algorithm exists.