Algorithms

What is an algorithm?

• A list of step by step instructions that accomplish a task.

• A random collection of numbers.

• A type of computer hardware.

• A programming language.

Which of the following is defined as putting steps in an order?

• Sequencing

• Selection

• Iteration

Which of the following is defined as deciding which steps to do next (if statements)?

• Sequencing

• Selection

• Iteration

Which of the following is defined as doing some steps over and over (loops)?

• Sequencing

• Selection

• Iteration

What is a heuristic technique used for in algorithms?

• A heuristic technique is designed for solving a problem more quickly when classic methods are too slow or for finding an approximate solution when classic methods fail to find any exact solution.

• A heuristic technique is used to guarantee the optimal solution for every problem.

• A heuristic technique is only used for sorting algorithms.

• A heuristic technique is a method that always provides the exact answer in polynomial time.

Efficiency is a measure of how many steps are needed to complete an algorithm.

• True

• False

Algorithms with a polynomial efficiency including n², n³, n⁴ or lower are said to run in a ______ amount of time.

• reasonable

• infinite

• exponential

• impossible

Algorithms with exponential: 2ⁿ, 3ⁿ, 4ⁿ or factorial: x! efficiencies are examples of algorithms that run in an ______ amount of time.

• unreasonable

• reasonable

• linear

• constant

Refer to the graph of efficiencies (times). Which type of algorithm is represented by the steepest curve labeled 'Unreasonable'?

• Exponential

• Group Raffle

Reasonable vs. Unreasonable time

We can categorize the run time of an algorithm according to how the number of steps increases as the input size increases. 

• Which of the following algorithm efficiencies would NOT run in Reasonable Time? 

• Constant

• Linear

• Polynomial functions such as:

  n-squared

  and

  n-cubed

• Factorial