Start by understanding how the standard Huffman coding algorithm works for binary trees (alphabet size 2) and generalize the merging process to handle ternary trees (alphabet size 3).

Consider how the priority queue (min-heap) should be modified to accommodate merging three nodes at a time instead of two, ensuring the tree remains optimal for ternary encoding.

Analyze the edge cases where the total number of symbols isn't divisible by 2 (for binary) or 3 (for ternary), and determine how to handle leftover nodes during the merging process to maintain optimality.