CS 455 Lecture Notes

Week One, Tuesday: Introduction

Instructor and Teaching Assistant

Handouts

• Student Questionaire
• Programming Style Guidelines

Please complete the student questionaire in class and pass it forward. Remote (ITV) students can use courier, fax, or e-mail.

Review of Introduction to Programming

• Data types: int, float, char, etc.
• Decision and loop structures: if(), switch(), while(), for(), etc.
• Function calls and the procedural paradigm.
• Recursion.
• Arrays and strings.
• Pointers.
• Abstract data types and the C "struct" data structure.
• Data modeling and nested structs.
• File I/O.

Program Specification and Design

1. Specify the input and output.
2. Design the algorithm and data structures.
3. Translate the algorithm into a programming language such as C++.
4. Test and debug the program.

The software life-cycle:

1. Analysis and specification of the task.
2. Design of the algorithms and data structures.
3. Implementation (coding).
4. Testing.
5. Maintenance and evolution of the system.
6. Obsolescence.

Algorithm Analysis

Algorithms in daily life. Swim meet example. Seeding swimmers requires sorting them on swimming speed. How do we sort the cards? Each card is a data object that holds information about a swimmer.

Testing and Debugging

1. You must know what output a correct program should produce for each test input.
2. The test inputs should include those inputs that are most likely to cause errors.

Debugging tips:

1. Never start changing suspicious code on the hope that the change "might work better."
2. Discover exactly why a test case is failing and limit your changes to corrections of known errors.
3. After correcting a known error, rerun all test cases (regression testing).