CS211 Data Structures

1. CS211Data Structures Sami Rollins srollins@mtholyoke.edu Fall 2004

2. Introduction • Course Website • Syllabus • Academic Dishonesty • Tentative Calendar

3. Administrative Information • Class web page http://www.mtholyoke.edu/courses/srollins/cs101/

4. Assignments • Reading – Chapter 1 • Homework 0 – due Monday

5. Computer Hardware • Main memory • Secondary memory • CPU • Input devices • Output devices

6. Computer Software • Operating system • Examples? • Applications • Examples? • How is a new application developed?

7. Computer Programs • At the lowest level – machine instructions • 00000111000 • One step up – assembly language • ADD A • More user friendly – high level languages • C = A + B; • Examples?

8. Translation • High level language must be translated into a language the computer can understand High-level Code Compiler Machine Instructions

9. Writing Programs • Understand requirements • Write an algorithm • Implement your algorithm • Test your code

10. What is an algorithm? • A specific set of instructions • An algorithm to make a PBJ sandwich?

11. Hello World /* * Name: Sami Rollins * Source file name: hello.c * My first "hello, world" program in C. */ #include <stdio.h> //the main function int main (void) { //print the phrase printf("Hello, world!"); return(0); }

12. Errors • You WILL have errors in your programs • Syntax Errors • Compiler doesn’t understand code • Ex. – printf(Hello, world!”); • Sometimes error messages don’t match problem • Logic • Program runs, but doesn’t do what you want • Ex. – printf(“Hell, world!”); • Can be hard to track down