Coding Exercises: Array Algorithms
You can do these exercises with either for or
for-each loops. Practice both!
Finding a maximum value
Write a function that takes an array of double values as input and returns the maximum value. Write a test function and several unit tests.
findMax(ArrayList({1.0, 2.1, 5.3})) -> 5.3
findMax(ArrayList({-35.0, 90.1, 0.0, 6.7})) -> 90.1Filtering a list
Write a function that takes an ArrayList of integer scores, and returns an ArrayList representing the scores below 50.
Demonstrate that the function works. Optional: write unit tests.
filterBadScores(ArrayList({51, 49, 37, 100})) -> ArrayList({49, 37})
filterBadScores(ArrayList({92, 89, 90, 99})) -> ArrayList({})Transforming a list
(Re)write a reverse() function that returns the
reverse of a single string. Then, using this function, write a
function reverseAll() takes an array of Strings and
returns a new array containing the same strings, but with each
string reversed.
Demonstrate that the function works. Optional: write unit tests.
reverseAll({"abcd", "xyz"}) -> {"dcba", "zyx"}
reverseAll({"1234", "5678"}) -> {"4321", "8765"}
reverseAll({"racecar", "tacocat", "izzi"}) -> {"racecar", "tacocat", "izzi"}Constructing a sequence
Write a function that takes a single integer n and
returns an array of integers containing the first n
terms of the Fibonacci sequence.
fibonacci(2) -> {1, 1}
fibonacci(3) -> {1, 1, 2}
fibonacci(4) -> {1, 1, 2, 3}
fibonacci(5) -> {1, 1, 2, 3, 5}Demonstrate that the function works. Optional: write unit tests.
Bonus Challenge: Generate prime numbers
Write a function that returns the first n prime
numbers in an array or ArrayList.
prime(3) -> {2, 3, 5}
prime(5) -> {2, 3, 5, 7, 11}