CS 101 Problem Solving and Structured Programming in C

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CS 101Problem Solving and Structured Programming
in C

• Sami Rollins
• srollins_at_mtholyoke.edu
• Spring 2003

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Introduction

• What is computer programming?
• What is this class about?
• Who should take this class?

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Administrative Information

• Class web page
• http//www.mtholyoke.edu/courses/srollins/cs101/

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Assignments

• Reading Chapter 1
• Homework 0 due Monday

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Computer Hardware

• Main memory
• Secondary memory
• CPU
• Input devices
• Output devices

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Computer Software

• Operating system
• Examples?
• Applications
• Examples?
• How is a new application developed?

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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?

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Translation

• High level language must be translated into a
  language the computer can understand

High-level Code
Compiler
Machine Instructions
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Writing Programs

• Understand requirements
• Write an algorithm
• Implement your algorithm
• Test your code

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What is an algorithm?

• A specific set of instructions
• An algorithm to make a PBJ sandwich?

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Hello World

• /
• Name Sami Rollins
• Source file name hello.c
• My first "hello, world" program in C.
• /
• include ltstdio.hgt
• //the main function
• int main (void)
• //print the phrase
• printf("Hello, world!")
• return(0)

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Errors

• You WILL have errors in your programs
• Syntax Errors
• Compiler doesnt understand code
• Ex. printf(Hello, world!)
• Sometimes error messages dont match problem
• Logic
• Program runs, but doesnt do what you want
• Ex. printf(Hell, world!)
• Can be hard to track down