Quiz 02 sample questions
The quiz will have three questions, and cover material through the end of the List
topics.
In the first question, you will read some code and write a concise, high-level, English description of the code’s action. For example:
public static List<Integer> mystery(List<Integer> l, int i) {
List<Integer> r = new ArrayList<>();
for (int j = i; j < l.size(); j++) {
r.add(l.get(j));
}
return r;
}
In the second question, you’ll identify a logic error in a short snippet of code. That is, you will find a conceptual error, not an error that the compiler would catch. Here is an example:
/**
* Swaps the `i`th and `j`th elements of the List `l`.
* Assume 0 <= i <= j <= l.size().
*/
public static void swap(List<Integer> l, int i, int j) {
l.set(i, l.get(j));
l.set(j, l.get(i));
}
In the final question, you will write a short class or method according to a textual description. For example, a question might state:
Write a method static List<Integer> concatenate(List<Integer> l1, List<Integer> l2)
. concatenate
should return, as a new list, all the elements of l1
followed by all the elements of l2
, in the order they appeared. Your code must not modify l1
or l2
.
For example, with an input of l1 = [1, 2, 5], l2 = [2, 4, 1]', it should return the list
[1, 2, 5, 2, 4, 1]`.
Assume List
and ArrayList
are correctly imported.
You can check your answers here.