# teaching machines

## CS 145 Lecture 2 – More data, more instructions

### Agenda

• what does this do?
• literals vs. variables
• a few more types (int, char, boolean)
• penny RAM
• a few more instructions (cos, pow)
• Javadoc
• String

### What does this do?

1. int a = 7;
int b = 3;
b = a + b;
2. int i;
System.out.println(i);
3. int i = 100;
System.out.println(i / 0);

### Code

#### Day2.java

package preexam1;

public class Day2 {
public static void main(String[] args) {
double myNum = 6.7;
int brettsFavoriteNumber = 9;
char debrasFavoriteLetter = 'd';
boolean isNickAPackersFan = false; // true

//    float foo;
//    long bigNumber;
//    short smallNumber;
//    byte aReallySmallNumber;

int l1 = (int) 13.6;
int l2 = (int) 23.0;

//    int foo = 92384920348203948230942309;

System.out.println("A really big int:");
System.out.println(Integer.MAX_VALUE);
System.out.println(Integer.MIN_VALUE);

System.out.println(l1);

//    double h = square root of l1 squared + l2 squared;
//    double h = Math.sqrt(0.0 / 0.0);
String label = "The hypotenuse:";
System.out.println(label);
double h = Math.sqrt(l1 * l1 + l2 * l2);

System.out.println(h);

int nSiblings = 1;
String gavInfo = "Gavin has " + nSiblings + " siblings";
System.out.println(gavInfo);
}
}


### Prelab

Please sign up for an account at Practice-It. Sign up under UWEC, and add CS 145 as one of your courses. Before 8 AM on Monday, complete:

• Self-check 2.4
• Self-check 2.8
• Exercise 2.1

No credit will be given after 8 AM.

### Haiku

Strings, celebrities!
They’re always getting quoted
They’re sure characters