13.6 Recursion Practice



Write a method called isPrime which returns true if the given integer is prime and false otherwise. This is similar to the Chapter 11 problem, but this time write your method using recursion.

In your main method, include a Scanner so the user can check as many numbers as they want until they enter -1.


Note: There are more complex solutions, but this is the fastest one within the scope of this chapter.

Practice template: practice/all-star.java

Solution: solutions/all-star.java

Merge Sort (Difficult)!

Code a recursive merge sort algorithm that only uses the given parameter array, and creates no other array in the process.

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