Question $12$

In Huffman coding, which of the following would

guarantee that characters $x$ and $y$ have identical code

lengths?

In the original data to compress, the first occurrence of $x$ is

adjacent to the first occurrence of $y.$

$x$ and $y$ appear adjacent to each other in sorted order after

the initial sort of the algorithm.

When drawing a character at random from the text to

compress, every character has an equal probability of

being drawn.

The algorithm contains randomization, so nothing about

the input can guarantee any two characters have the same

code length.