23
Flowchart of a linear algorithm
Textbook: pp. 59–61
GoalKnow what a linear algorithm is and read it as words and as a flowchart.
New words
linear algorithm · chiziqli algoritmgreeting card · tabriknomato fold · buklamoqbattery · batareyka
Explanation
An algorithm whose actions are done one after another is called a linear algorithm. Its flowchart has only ovals and rectangles. The ovals stand only at the beginning and the end, never in the middle. A linear algorithm can be written in two ways: with words (a numbered list) or as a flowchart.
Worked examples
Algorithm “Paper plane”: 1) take a sheet, 2) fold it in the middle, 3) fold the corners inwards, 4) spread the wings.
A robot reaches the battery in 3 actions: → → ↑. The flowchart has 2 ovals, 3 rectangles and 4 arrows.
Class activity
“Two ways”: children first write the algorithm “Boiling an egg” as a numbered list, then glue paper shapes into a flowchart.
Practice
1
Which shapes does the flowchart of a linear algorithm have?
ovals, rectangles and arrows
2
Can ovals be in the middle of an algorithm?
No, only at the beginning and the end
3
In a linear algorithm of 4 actions, how many rectangles and how many arrows are there?
4 rectangles, 5 arrows