Unit 6 Test - Algorithms

Which of the following is true of algorithms?

• Algorithms may have an infinite set of instructions

• Not every algorithm can be constructed using combinations of sequencing, selection, and iteration

• Algorithms must be expressed using a programming language

• Not all problems can be solved with an algorithm

The following algorithm is followed by a teacher every morning when they get to their classroom:

1. Unlock classroom door.

2. Turn on the power.

3. Turn on the computer.

4. Write learning objectives on the board.

5. Check emails.

6. Get coffee.

7. Greet students as they arrive.

• Execution

• Sequencing

• Selection

• Iteration

Which of these algorithms will move the robot along the same path as the algorithm shown?

• 
• 
• 
• 

A school bus driver is deciding what order to pick up the students in. They want to pick an order that minimizes the gas the school bus has to use. What term best defines the kind of problem?

• An undecidable problem

• An optimization problem

• A decision problem

• An efficiency problem

The algorithm shown is used to find the smallest element in a list of numbers.

By modifying one of the lines in the program it is possible to make the algorithm find the LARGEST element. Which line would need to be modified and how?

• Line 04 becomes IF (num > target)

• Line 01 becomes target <- list[2]

• Line 04 becomes IF (num = target)

• Line 01 becomes list[0] <- target

Assume that sum is initialized to 0. Which of the following algorithms finds the sum of the even integers from 2 to 20?

• 
• 
• 
• 

This graph shows the efficiencies of two different sorting algorithms. Which of the following is most efficient?

• Algorithm B is more efficient than Algorithm A.

• They are equally efficient.

• They are solving an undecidable problem so we cannot say which is more efficient.

• They have different efficiencies depending on input size.

A school is creating lunch schedules for its students. The students may be sorted into one of three possible lunch groups: Lunch 4A, Lunch 4B, or Lunch 4C.

The school has determined that finding the absolute best lunch schedule cannot be solved in a reasonable time. What might the school take advantage of in order to help solve their problem in time for school to start?

• heuristics

• Two algorithms that solve the same problem that also have the same efficiency

• This problem is unreasonable AND undecidable.

• the Halting problem

Which of the following algorithmic efficiencies would be considered unreasonable?

• Polynomial

• Exponential

• Constant

• Linear

Which of the following is the best example of an undecidable problem?

• Sorting the same array of numbers using multiple sorting algorithms.

• Writing an algorithm that runs in O(n).

• The Traveling Salesman Problem

• The Halting Problem