Algorithm Constructs

Algorithm Constructs

1. Sequence

   • A sequence is a number of instructions that are processed one after the other.
     • DECLARE count SET countTO 1 OUTPUT the value of count

2. Assignment

   • Assignment is used to store the value of an expression into a variable.
     • DECLARE studentName SET studentName TO Bob

3. Selection and Condition (IF, IF ELSE)

   • A selection statement uses a condition to select, or determine, the next line of the program that is to be executed.
     • CALCULATE totalCost IF (totalCost > $10) THEN OUTPUT 'no delivery charge' ELSE OUTPUT '$5 delivery charge' ENDIF OUTPUT 'thankyou'

4. Iteration

   • 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.
     • DECLARE count SET count TO 0 FOR count = 1 to 10 OUTPUT count END FOR OUTPUT ‘finished’

5. Modularisation

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