Chapter 8: More on the Repetition Structure

1. Chapter 8:More on the Repetition Structure Introduction to Programming with C++ Fourth Edition

2. Objectives • Show the posttest repetition structure in pseudocode and in a flowchart • Code a posttest loop using the C++ do while statement • Nest repetition structures Introduction to Programming with C++, Fourth Edition

3. Posttest Loops • Condition is evaluated with each repetition, or iteration, of the loop • Evaluation occurs after the instructions within the loop are processed Introduction to Programming with C++, Fourth Edition

4. Posttest Loops (continued) Introduction to Programming with C++, Fourth Edition

5. Coding the Posttest Loop • In the do while statement, the programmer must supply the loop condition to be evaluated • Loop condition: • Must be a Boolean expression (true or false) • Can contain variables, constants, functions, methods, arithmetic operators, comparison operators, and logical operators Introduction to Programming with C++, Fourth Edition

6. Coding the Posttest Loop (continued) • Programmer must also supply statements to be processed when the loop condition evaluates to true • If more than one statement needs to be processed, they must be entered as a statement block Introduction to Programming with C++, Fourth Edition

7. Syntax of the C++ do while Statement Introduction to Programming with C++, Fourth Edition

8. Nested Repetition Structures • Inner loop - placed entirely within another loop, called the outer loop Introduction to Programming with C++, Fourth Edition

9. Nested Loops Used by a Clock Introduction to Programming with C++, Fourth Edition

10. Summary • Posttest repetition structure evaluates a condition after the loop body • Use the do while statement to code a posttest loop • You can also use nested repetition structures • Make sure the outer loop completely contains the inner loop Introduction to Programming with C++, Fourth Edition