CS 200 - Programming I Jim Williams, PhD

Who Am I? My Interests: CS Education, specifically the teaching and learning of programming. PhD in Computer Science, minor in Educational Psychology Husband, Father, Coach, Traveller, ... http://pages.cs.wisc.edu/~jimw/

Comp Sci 200 - Programming I What is Computer Science & Programming? Tracing a Java Program Organization of Course Who is here? Programming Process

What is Computer Science? What is Programming? With a name like computer science, you might think it is all about the computer. Core principles: Abstractions and algorithms This course: Learning to give instructions to the computer. Read and Write Java

What is Computer Science? The study of the computer itself as well as how computers are applied to solve problems in any field. What is Programming? Designing algorithms and writing them in a language a computer can execute.

Enjoyment and Satisfaction Lots of puzzles, problem solving and challenge Opportunity to create something from nothing Opportunity to apply to any field Many enjoy these aspects of Computer Science and find a lot of satisfaction when successful.

A Java Program import java.util.Scanner; public class ReadNumber { public static void main(String[] args) { Scanner input = new Scanner(System.in); double num = input.nextDouble(); System.out.println("Number entered: " + num); } Java is a text language for controlling the computer. Programs are called "code" for a reason. Decode (read) "convert (a coded message) into intelligible language." [Google Dictionary]

Java Visualizer Demo Link available on right side of course website. https://cs200-www.cs.wisc.edu/wp/

https://cs200-www.cs.wisc.edu/wp/ http://pages.cs.wisc.edu/~cs200

Organization of Course: Study Cycle

When Women Stopped Coding http://www.npr.org/sections/money/2014/10/21/357629765/when-women-stopped-coding

Who is here?

Understand vs. Apply Steph Curry, NBA Golden State Warriors Basketball Analogy Demonstration vs. Practice Declarative Knowledge vs Procedural Knowledge Importance of Practice for learning If you watch the same video or even 10 different videos on how to shoot a basketball do you get better at shooting a basketball? Steph Curry, NBA Golden State Warriors

Declarative and Procedural Knowledge Declarative: Knowledge about something talk about a bike CS terms and Java syntax Procedural: Knowing how to do something ride a bike solve a problem systematically write in Java

Edit-Compile-Run Cycle From the command-line: notepad (Editor) javac (Compiler) java (Virtual Machine)

File name Cat.txt Cat.java Cat.class Cat For the class named Cat, what is the name of the file that the compiler creates and is provided to the Java Virtual Machine to run? Cat.class

Compile For the class named Cat, what command would compile the class? notepad Cat.java javac Cat.java java Cat.java java Cat For the class named Cat, what command would compile the class? javac Cat.java

Edit-Compile-Run Cycle Users Editor (Virtual) Machine Compiler Hello.java Hello.class Computer Files Programmer

Various Errors Naming/Saving Syntax/Compile time Runtime & Logic Files Editor (Virtual) Machine Compiler Hello.java Hello.class Computer Files Programmer

Programming Process Study the Problem Design an Algorithm to Solve the Problem Write in Code (e.g., Java) Compile the Code Run the code Repeat

Problem Obtain 3 numbers from the user. IF the 3 numbers could be lengths of the sides of a triangle, output "COULD be lengths of sides of a triangle" OTHERWISE output "Cannot be lengths of sides of a triangle" import java.util.Scanner; public class ClassNameHere { public static void main(String[] args) { Scanner input = new Scanner(System.in); double one = input.nextDouble(); double two = input.nextDouble(); double three = input.nextDouble(); if ( one + two > three && one + three > two && two + three > one) { System.out.println("COULD be the lengths of the sides of a triangle."); } else { System.out.println("Cannot be the lengths of the sides of a triangle."); } Reference: Frank Ackerman

Problem Write a program to calculate the cost to carpet a floor. Tips for Solving Programming Problems Java Visualizer starting point