Which operator needs to be overridden in order to use std::set in the C++ code?

Question

This is an interview question.

Referring to the sample code, which one of the operators needs to be overridden in order to use st

Answer 1

To speed up the enforcement of no duplicate elements and generally checking if element is in its usually some sort of a tree and only needs operator <. (The only usage of less is enforced by the standard, the rest is just the avarage implementation)