Quiz 4

Wednesday

With a piece of paper, write down your name and answers to the following questions.

Consider the following program?

public final class Program {
	public static void main(final String[] args) {
		System.out.println("mysteriousOne output:");
		mysteriousOne(3);

		System.out.println("mysteriousTwo output:");
		mysteriousTwo(3);

		System.out.println("mysteriousThree output:");
		mysteriousThree(3);
	}

	private static void mysteriousOne(final int n) {
		System.out.println(n);
		if (n > 1)
			mysteriousOne(n - 1);
	}

	private static void mysteriousTwo(final int n) {
		if (n > 1)
			mysteriousTwo(n - 1);
		System.out.println(n);
	}

	private static void mysteriousThree(final int n) {
		System.out.println(n);
		if (n > 1)
			mysteriousThree(n - 1);
		System.out.println(n);
	}
}

1. What is the base case for the mysteriousThree method?

   Answer: n <= 1.

2. What is the recursive case for the mysteriousThree method?

   Answer: n > 1.

3. What is the output of this program?

   Answer:

   mysteriousOne output:
3
2
1
mysteriousTwo output:
1
2
3
mysteriousThree output:
3
2
1
1
2
3


Student Performance and Statistics

A histogram of student performance on percentage grades for Quiz 4 on Wednesday.

A table showing the average performance for each question in Quiz 4 on Wednesday.

Friday

With a piece of paper, write down your name and answers to the following questions.

Consider the following program?

public final class Program {
	public static void main(final String[] args) {
		mysteriousTwo(3);
	}

	private static void mysteriousTwo(final int n) {
		if (n < 1)
			return;
		mysteriousTwo(n - 1);
		mysteriousOne(3);
	}

	private static void mysteriousOne(final int n) {
		if (n <= 1) {
			System.out.println("Hurrah");
			return;
		}
		System.out.println("Hip");
		mysteriousOne(n - 1);
	}
}

1. What is the base case for the mysteriousOne method?

   Answer: n <= 1.

2. What is the recursive case for the mysteriousOne method?

   Answer: n > 1.

3. What is the output of this program?

   Answer:

   Hip
Hip
Hurrah
Hip
Hip
Hurrah
Hip
Hip
Hurrah


Student Performance and Statistics

A histogram of student performance on percentage grades for Quiz 4 on Friday.

A table showing the average performance for each question in Quiz 4 on Friday.