User blog comment:Nayuta Ito/Introduction to AAN/@comment-29014792-20160805233152/@comment-25337554-20160807032716

Then how does it correspond to the original description? What is "in the left"? If in this case K=comma, right? I guess K={y}. What is "jump into"? I can't continue the process with only y.
 * Find the seperator in the left and copy it to K.
 * Replace the previous entry to '0 K 1'.
 * Jump into K and continue the process.