✍U10 Algorithms Vocabulary

Problem

a general description of a task that can (or cannot) be solved with an algorithm

Algorithm

a finite set of instructions that accomplish a task.

Sequencing

putting steps in order; the application of each step of an algorithm in the order in which the code statements are given

Selection

deciding which steps to do next; determines which parts of an algorithm are executed based on a condition being true or false. The use of conditional statements or “if-statements” is a form of selection.

Iteration

doing some steps over and over; a repeating portion of an algorithm. repeats a specified number of times or until a given condition is met. 

Efficiency

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

Linear Search

a search algorithm which checks each element of a list, in order, until the desired value is found or all elements in the list have been checked.

Binary Search

a search algorithm that starts at the middle of a sorted set of numbers and removes half of the data; this process repeats until the desired value is found or all elements have been eliminated.

Reasonable Time

algorithms with a polynomial efficiency or lower (constant, linear, square, cube, etc.) are said to run in a reasonable amount of time.

Unreasonable Time

Algorithms with exponential or factorial efficiencies are examples of algorithms that run in this amount of time.

Heuristic

provides a "good enough" solution to a problem when an actual solution is impractical or impossible

Decision Problem

a problem with a yes/no answer  (e.g., is there a path from A to B?)

Optimization Problem

a problem with the goal of finding the "best" solution among many (e.g., what is the shortest path from A to B?)

Undecidable Problem

a problem for which no algorithm can be constructed that is always capable of providing a correct yes-or-no answer

Sequential Computing

a computational model in which operations are performed in order one at a time

Parallel Computing

a computational model where the program is broken into multiple smaller sequential computing operations, some of which are performed simultaneously

Distributed Computing

a computational model in which multiple devices are used to run a program.

Speedup

the time used to complete a task sequentially divided by the time to complete a task in parallel, measures speed and efficiency