Standard Pseudocode Procedure

1. Write only one statement per line. Each statement in your pseudocode should express just one action for the computer. In most cases, if the task list is properly drawn, then each task will correspond to one line of pseudocode. Consider writing out your task list, then translating that list into pseudocode, then gradually developing that pseudocode into actual, computer-readable code.
   • Task list:
     • Read the name, hourly rate, hours worked, deduction rate
     • Perform calculations
     • gross = hourly rate * hours worked
     • deduction = gross pay * deduction rate
     • net pay = gross pay – deduction
     • Write name, gross, deduction, net pay
   • Pseudocode:
     • READ name, hourlyRate, hoursWorked, deductionRate
     • grossPay = hourlyRate * hoursWorked
     • deduction = grossPay * deductionRate
     • netPay = grossPay – deduction
     • WRITE name, grossPay, deduction, netPay
2. Capitalize the initial keyword of each main direction. In the above example, READ and WRITE are capitalized to indicate that they are the primary functions of the program. Relevant keywords might include: READ, WRITE, IF, ELSE, ENDIF, WHILE, ENDWHILE, REPEAT, and UNTIL.
3. Write what you mean, not how to program it. Some programmers write pseudocode like a computer program: they write something like “if a % 2 == 1 then“. However, most readers must stop to reason through lines that are so abstractly symbolic. It is easier to understand a verbal line like “if an odd then“. The clearer you are, the more easily people will be able to understand what you mean.
4. Leave nothing to the imagination. Everything that is happening in the process must be described completely. Pseudocode statements are close to simple English statements. Pseudocode does not typically use variables but instead describes what the program should do with close-to-real-world objects such as account numbers, names, or transaction amounts.
   • Some examples of valid pseudocode are:
     • If the account number and password are valid then display the basic account information.
     • Prorate the total cost proportional to the invoice amount for each shipment.
   • Some examples of invalid pseudocode are:
     • let g=54/r (Why: Do not use variables. Instead, you should describe the real-world meaning.)
     • do the main processing until it is done (Why: You should be specific about what ‘main processing’ means, and what qualifies the process as ‘done’.)
5. Use standard programming structures. Even if there is no standard for pseudocode, it will be easier for other programmers to understand your steps if you use structures from existing (sequential) programming languages. Use terms like “if“, “then“, “while“, “else“, and “loop” the same way that you would in your preferred programming language. Consider the following structures:
   • if CONDITION then INSTRUCTION – This means that a given instruction will only be conducted if a given condition is true. “Instruction”, in this case, means a step that the program will perform. “Condition” means that the data must meet a certain set of criteria before the program takes action.
   • while CONDITION do INSTRUCTION – This means that the instruction should be repeated again and again until the condition is no longer true.
   • do INSTRUCTION while CONDITION – This is very similar to “while CONDITION do INSTRUCTION“. In the first case, the condition is checked before the instruction is conducted, but in the second case, the instruction will be conducted first. So in the second case, INSTRUCTION will be conducted at least one time.
   • for a = NUMBER1 to NUMBER2 do INSTRUCTION – This means that “a“, a variable, will be automatically set to NUMBER1. “a” will be increased by one in every step until the value of the variable reaches NUMBER2. You can use any name for the variable that you think fits better than “a“.
   • function NAME (ARGUMENTS): INSTRUCTION – This means that every time a certain name is used in the code, it is an abbreviation for a certain instruction. “Arguments” are lists of variables that you can use to clarify the instruction.

Use blocks to structure steps. Blocks are syntactic tools that tie several instructions together into one instruction. You can use blocks to order information (say, steps in Block 1 always come before steps in Block 2) or simply to wrap information (say, Instruction1 and Instruction2 are thematically related). In general, indent all statements that show “dependency” on another statement. There are two ways to do this.

• Using curled brackets:
  • {
  • INSTRUCTION1
  • INSTRUCTION2
  • …}

• Or using spaces. When using spaces, every instruction of the same block has to start at the same position. Blocks within blocks have more spaces than the parent block. An instruction from a parent block ends the child block, even if there is an instruction later with the same amount of spaces in front.
  • BLOCK1
  • BLOCK1
    • BLOCK2
    • BLOCK2
      • BLOCK3
    • BLOCK2
      • BLOCK3
  • BLOCK1