Pseudocode

1. Pseudocode Developing Your Program Logic

2. What is Pseudocode • A computer program is the representation of an "algorithm" (an unambiguous set of steps, in a particular order, which when followed will solve the problem) • Pseudocode is the representation of these steps in "structured English" • Steps must be clear (i.e. unambiguous) • Order must be specified • When the steps (i.e., instructions) are followed, they must produce a solution to the specified problem

3. Why Develop Logic Using Pseudocode? • The alternative: just enter Java code? • logic is not clear • computer language (e.g., Java) is too detailed and lengthy • focus moves to language syntax • is not conducive to successive refinement • Flowcharts and other design tools are suitable alternatives to pseudocode

4. Successive Refinement • Equally applicable whether you use pseudocode or flowcharting • Start at the "top" which is a one line statement of your program's purpose and break it down by stages into greater and greater levels of detail • Successive refinement stops when there is enough detail to write the program • Each pseudocode statement or flowchart symbol is a basic building block (like a tinker toy) • these are assembled into complex structures • assembled in specific ways

5. Applying Successive Refinement • Start with a one-line statement of the problem • Break down into 3-5 steps • Break down each of these into 3-5 steps • Continue this process (i.e. successive refinement) until each step will become one or a small number of Java statements

6. Program (Logic) Planning • Look at the output (desired product) • Determine what inputs are necessary to allow the creation of desired output • Design the logic (steps) to collect the input and build the desired output • Often this leads to a general program logic flow of • input • processing • output

7. Advantages Derived from Using Pseudocode • Good tool for program logic planning • Can use to review system logic with user • Can document logic for system maintenance