int a = 1;
int b = 1;
int sum = a+b;
System.out.println("Decimal Sum: " + sum); // Print Decimal Sum
System.out.println("Binary Sum: " + Integer.toBinaryString(sum)); // Print and Convert to Binary Sum
public class IntByValue {
public static void changeInt(int n) {
System.out.println("In changeInt method");
System.out.println("\tBefore n += 10: n = " + n); // prints 5
n = n += 10;
System.out.println("\tAfter n += 10: n = " + n); // prints 10
}
public static void main(String[] args) {
int n = 5;
System.out.println("Main method before changeInt(n): n = " + n); // prints 5
changeInt(n);
System.out.println("Main method after changeInt(n): n = " + n); // still prints 5
}
}
IntByValue.main(null);
public class IntByReference {
private int value;
public IntByReference(Integer value) {
this.value = value;
}
public String toString() {
return (String.format("%d", this.value));
}
public void swapToLowHighOrder(IntByReference i) {
if (this.value > i.value) {
int tmp = this.value;
this.value = i.value;
i.value = tmp;
}
}
public static void swapper(int n0, int n1) {
IntByReference a = new IntByReference(n0);
IntByReference b = new IntByReference(n1);
System.out.println("Before: " + a + " " + b);
a.swapToLowHighOrder(b); // conditionally build swap method to change values of a, b
System.out.println("After: " + a + " " + b);
System.out.println();
}
public static void main(String[] ags) {
IntByReference.swapper(21, 16);
IntByReference.swapper(16, 21);
IntByReference.swapper(16, -1);
}
}
IntByReference.main(null);
/// Primitive Data Type "int" within an array
public class Example {
public static void main(String[] args) {
int[] numbers = {1, 2, 3, 4, 5}; // define array called numbers that have 5 int values
int sum = 0;
for (int i = 0; i < numbers.length; i++) { // iterate over array to sum the int values
sum += numbers[i];
}
System.out.println("Sum of numbers: " + sum); // outputs the sum
}
}
Example.main(null);
/// Primitive Data Type "double" within an array
public class DoubleArrayExample {
public static void main(String[] args) {
// declare an array of doubles
double[] myArray = { 1.99, 5.5, 20.1, 0.9999 }; // declare an array with 4 values
// print out the values of the array
for (int i = 0; i < myArray.length; i++) {
System.out.println("Element " + i + " = " + myArray[i]); // loop through the array using a for loop and print out each element in the array. Note that we use the double primitive type to declare the array and assign values to it.
}
}
}
DoubleArrayExample.main(null);
/// Primitive Data Type "boolean" within an array
public class BooleanArrayExample {
public static void main(String[] args) {
// declare an array of booleans
boolean[] myArray = { true, true, false, false }; // declare array with boolean data types
// print out the values of the array
for (int i = 0; i < myArray.length; i++) {
System.out.println("Element " + i + " = " + myArray[i]);
}
}
}
BooleanArrayExample.main(null);
/// Primitive Data Type "char"
import java.util.Random;
public class CharExample {
public static void main(String[] args) {
Random rand = new Random(); // create random object to generate random number
char[] vowels = {'a', 'b', 'c', 'd', 'e'}; // array of vowels
char randomVowel = vowels[rand.nextInt(vowels.length)]; // next Int method of the rand object generates a random integer that retrieves a random vowel
System.out.println("The random letter A-E is " + randomVowel);
}
}
CharExample.main(null);
import java.util.Arrays;
import java.util.Random;
public class WrapperClassesExample {
public static void main(String[] args) {
// int
Integer num = Integer.valueOf(42);
Integer[] arr = {Integer.valueOf(1), Integer.valueOf(2), Integer.valueOf(3), Integer.valueOf(4), Integer.valueOf(5)};
System.out.println("The number is " + num);
System.out.println("The third element of the array is " + arr[2]);
// double
Double d = Double.valueOf(1.99);
System.out.println("The double " + d);
// boolean
Boolean b = Boolean.valueOf(true);
System.out.println("The boolean is " + b);
// char
Character c = Character.valueOf('z');
System.out.println("The value of char is " + c);
// Using substring method on String
String str = "Hello, World!";
String substr = str.substring(7, 12);
System.out.println("The substring is " + substr);
// Generating random numbers
Random rand = new Random();
Integer randNum = Integer.valueOf(rand.nextInt(1000));
System.out.println("The random number is " + randNum);
// Sorting an array
Arrays.sort(arr);
System.out.println("The sorted array is " + Arrays.toString(arr));
}
}
WrapperClassesExample.main(null);
- What are methods: Methods are code functions when called preform a specific function.
- What are Control Structures: A block of code that can change the path we take through those instructions, an example of this is a loop.
Mr. M's Code
- Diverse Array: Has loops and if statements and uses data types since it has int and arrays.
- Random: Generates type number greater than or equal to 0.0 and less than 1.0.
- Do Nothing by Value: Doesn't change #s locally and changes variables subvalues.
- Int by Reference: Value of int changes locally
- Menu: Use of cat, try, and while
public static Position findPosition(int num, int[][] intArr) {
for (int row=0; row < intArr.length; row++) {
for (int col=0; col < intArr[0].length; col++) {
if (intArr[row][col] == num) {
return new Position(row, col);
}
}
}
return null;
}
public static Position[][] getSuccessorArray(int[][] intArr) {
Position[][] newArr = new Position[intArr.length][intArr[0].length];
for (int row=0; row < intArr.length; row++) { // Forward Searching
for (int col=0; col < intArr[0].length; col++) {
newArr[row][col] = findPosition(intArr[row][col]+1, intArr); // // Assign the result of calling the 'findPosition' method to the current element in 'newArr'
}
}
return newArr;
}