The program development life cycle, decomposition and writing algorithms

Learning objectives

Describe the analysis, design, coding and testing stages of the program development life cycle, and state what each stage passes on to the next

Decompose a problem into its inputs, processes, outputs and storage, and explain how splitting a system into sub-systems makes a large problem manageable

Represent an algorithm as a structure diagram, as a flowchart and as pseudocode, and convert an algorithm from any one of these forms into another

Draw a flowchart using the correct symbols for a terminator, a process, a decision, an input or output and a sub-routine, following the standard direction of flow

Write pseudocode that uses assignment, INPUT and OUTPUT, IF and CASE selection, and FOR, WHILE and REPEAT loops, keeping the indentation consistent throughout

Read an algorithm written by somebody else, explain in words what it does, and suggest a change that makes it more efficient or easier to follow