به انگلیسی

Many values, one name

Computing · Programming · ages 15-16

Name ______________________ Date ____________

rainbowColours holds red, orange, yellow, green, blue, indigo and violet. What does rainbowColours[2] give?
- orange
- yellow
- green
What is a list?
- One value stored under many names
- A name with no values at all
- Many values stored under one name
Appending adds the new item to the end of the list.
Circle one: True False
An empty snack list gets "apples", "crackers", "grapes" and "nuts" appended in that order. What seat does "nuts" take?
Answer: ______________
After rainbowColours[1] = "pink", what sits in seat 1?
- pink
- orange
- red
Why does one list beat twenty separate variables for the same scores?
- Twenty names run faster
- One name holds them all, so the set stays tidy
- Variables cannot hold numbers
A list holds "b", "c" and "d". You insert "a" at seat 0. What seat does "d" sit in now?
- 3
- 2
- 4
A program reads slot 7 of a 7-item list and fails. What is the mistake?
- The list needs one more push first
- Slot 7 is invisible until printed
- Seats run 0 to 6, so slot 7 is past the end

Answer key

For grown-ups. Fold this page away before handing over the rest.

yellow · Seats count from 0: red is 0, orange is 1, so yellow sits in seat 2.
Many values stored under one name · A list bundles a whole collection under a single name.
True · Append grows the end, so the newcomer takes the next free seat.
3 · Four appends fill seats 0, 1, 2 and 3 in order, so the last one lands in seat 3.
pink · Assignment rewrites that slot, so seat 1 now holds pink instead of orange.
One name holds them all, so the set stays tidy · A single name keeps the whole set together with zero clutter.
3 · Inserting at the front pushes every older item one seat up, so d moves from seat 2 to seat 3.
Seats run 0 to 6, so slot 7 is past the end · Seven items fill seats 0 to 6. Reaching for 7 is one too far.