ALGORMITHMIC CONSTRUCTS

ALGORMITHMIC CONSTRUCTS

1. Modularisation

   • Iteration is also called repetition and is used when something is repeated over and over again, so anything where the program goes round in a loop. Typically programmed using code such as WHILE, REPEAT and FOR statements
     • Pseudocode Example: DECLARE count SET count TO 0 FOR count = 1 to 10 OUTPUT count END FOR OUTPUT ‘finished

2. Iteration

   • Modularisation is used to reduce the complexity of a system by deconstructing it into independent units or modules.
     • Pseudocode Example: FUNCTION delivery_charge CALCULATE totalCost IF (totalCost > $10)  THEN OUTPUT  ‘no delivery charge’ ELSE OUTPUT  ‘$5 delivery charge’ ENDIF OUTPUT  ‘thankyou’ END FUNCTION

3. Selection and Condition

   • A selection statement uses a condition to select, or determine, the next line of the program that is to be executed. These statements help to make decisions and change the flow of a program. In many languages, there are two types of selection statements:
     • Pseudocode Example: CALCULATE totalCost IF (totalCost > $10) THEN OUTPUT   'no delivery charge' ELSE OUTPUT  '$5 delivery charge' ENDIF OUTPUT  'thankyou'

4. Sequence

   • A sequence is a number of instructions that are processed one after the other.
     • For example, a very simple algorithm for brushing teeth might consist of these steps: put toothpaste on toothbrush use toothbrush to clean teeth rinse toothbrush

5. Assignment

   • Assignment is used to store the value of an expression into a variable. In programming, this is exactly the same idea, except computers can remember anything not just numbers. Additionally, the variables are generally given more meaningful names that relate to the data they contain
     • Pseudocode Example: DECLARE studentName SET studentName TO Bob .