Exam 15: Recursion

Recursion is never absolutely required to solve a problem.

In the following code that uses recursion to find the factorial of a number, what is the base case? private static int factorial(int n) { If (n == 0) Return 1; Else Return n * factorial(n - 1); }

When recursive methods directly call themselves, it is known as __________.

Given the following code that uses recursion to find the factorial of a number, how many times will the else clause be executed if n = 5? private static int factorial(int n) { If (n == 0) Return 1; Else Return n * factorial(n - 1); }

In the following code that uses recursion to find the greatest common divisor of a number, what is the base case? public static int gcd(int x, int y) { If (x % y == 0) Return y; Else Return gcd(y, x % y); }

In the __________, the problem must be reduced to a smaller version of the original problem.

To use recursion for a binary search, what is required before the search can proceed?

The __________ is at least one case in which a problem can be solved without recursion.

A method is called from the main method for the first time. It then calls itself seven times. What is the depth of recursion?

Any problem that can be solved recursively can also be solved iteratively, with a loop.

Without a base case, a recursive method will call itself only once and stop.

In a recursive program, the number of times a method calls itself is known as the __________.

The recursive case does not require recursion so it stops the chain of recursive calls.

Recursion can be a powerful tool for solving repetitive problems and is an important topic in upper-level computer science courses.

A recursive method must have which of the following?

Whereas a recursive algorithm might result in faster execution time, the programmer might be able to design an iterative algorithm faster.

A recursive method can have only one base case.

The Towers of Hanoi is a mathematical game that is often used in computer science textbooks to illustrate the power of recursion.

The recursive binary search algorithm is a good example of repeatedly breaking a problem down into smaller pieces until it is solved.

The actions performed by the JVM that take place with each method call are sometimes referred to as __________.