← Reading Code · Lesson 2 of 3
Keep a table
When a program has more than one variable, keep a small table on paper: one column per variable, one row per line. Write the new value each time a line changes it.
For a = 2, b = a × 3, a = b − 1, the table goes: a is 2; b is 6; a becomes 5.
a = 2, then b = a × 3, then a = b − 1. What is a at the end?
A lesson is kept once you've answered the question and written at least 8 words. Nobody grades it; it stays on this device.