Parsing problem statement
The user wants a C++ solution for a machine learning ensemble problem, specifically adding the minimum number of models needed to change an ensemble's decision. I need to write concise code, use short variable names (<= 2 letters), and keep the explanation minimal. Let's start by understanding the input, which involves the number of classes N (2 ≤ N ≤ 1e5).
Understanding the problem
The problem involves determining the minimum number of new models to add to the ensemble to change its decision. The ensemble decision is based on the highest voting class, and if there's a tie, all tied classes are considered the winners. I need to find the classes that currently have the most votes and add a minimum number of models to disrupt the existing winners.
Analyzing decision change
To change the ensemble’s decision, we need the set of winners to differ from the original set. If there’s a unique highest class, we can promote the second-highest to tie, but this would still include the original winner. To truly change the decision, the final winner set should be different in some way, not just a tie.
Formulating the approach
If there’s a unique winner, adding votes to the second-highest class to reach the maxVal will change the decision. If there’s a tie, we need to break it by boosting one of the current winners to exceed the others. The strategy is to add the fewest votes necessary to change the decision.
Thought for 17s
