Unlike strings, lists and arrays are mutable. You can change them in place. The four operations you'll use constantly: add to the end, remove, update by position, and slice out a section.
Adding and removing
PYTHON
cities.append("Lagos") # add to end
cities.pop() # remove last
cities.remove("Accra") # remove by value
≈
JAVASCRIPT
cities.push("Lagos"); // add to end
cities.pop(); // remove last
cities.splice(0, 1); // remove by position
Compare → Same operations, different method names. Python appends; JavaScript pushes. Both pop. Removing by value is a one-liner in Python; JavaScript works by position with splice. Different syntax for a shared concept.
EXAMPLE
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YOUR TURN
Your turn → Updating by index replaces that slot. Add a fourth artist you admire, then remove the second one.
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Syntax has to be exact. Every quote, bracket and parenthesis needs its partner, and in Python the spaces at the start of a line count. One slip and the program won't run; the message will say where.
Slicing cuts a section out of a sequence: exactly like slicing a string, because both are sequences. Start included, end excluded.
EXAMPLE
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YOUR TURN
Your turn → Python can leave either side of the colon blank to mean 'from the start' or 'to the end'. Add a line that prints only the last two numbers, and one that prints everything except the first.
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Syntax has to be exact. Every quote, bracket and parenthesis needs its partner, and in Python the spaces at the start of a line count. One slip and the program won't run; the message will say where.
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