This document proposes algorithms to efficiently find the best parameter K for the emerging pattern-based classifier PCL. It first summarizes the PCL classifier and discusses how the parameter K impacts its performance. It then presents the rPCL and ePCL algorithms to determine the optimal K value. rPCL repeatedly subsamples the training data and evaluates different K values to find the best average accuracy. ePCL enhances rPCL by using an incremental pattern maintenance technique called PSM to avoid recomputing emerging patterns from scratch for each subsample, improving runtime efficiency. Experimental results show that finding the best K through these algorithms significantly improves PCL's accuracy.