Fibonacci and Extends
Using extend on fibonacci class
Fulfilling Collegeboard Standard
Skill 1.B: Determine code that would be used to complete code segments
- The code that would be used to complete code segments in this case are the while loop, for loop, and recursion. This assignment has us work with all of them
Skill 4.C: Determine if two or more code segments yield equivalent results
- By using the extends keyword and the jupyter notebook, we can easily compare the results of different loops
Skill 5.A: Describe the behavior of a given segment of program code
- This is done through commenting on each method, and you can see that each one is unique through how exactly the iteration happens
/*
* Creator: Nighthawk Coding Society
* Mini Lab Name: Fibonacci sequence, featuring a Stream Algorithm
*
*/
import java.util.ArrayList;
import java.util.HashMap;
import java.util.stream.Stream;
/* Objective will require changing to abstract class with one or more abstract methods below */
public class Fibo {
String name; // name or title of method
int size; // nth sequence
int hashID; // counter for hashIDs in hash map
ArrayList<Long> list; // captures current Fibonacci sequence
HashMap<Integer, Object> hash; // captures each sequence leading to final result
/*
Zero parameter constructor uses Telescoping technique to allow setting of the required value nth
@param: none
*/
public Fibo() {
this(10); // telescope to avoid code duplication, using default as 20
}
/*
Construct the nth fibonacci number
@param: nth number, the value is constrained to 92 because of overflow in a long
*/
public Fibo(int nth) {
this.size = nth;
this.list = new ArrayList<>();
this.hashID = 0;
this.hash = new HashMap<>();
//initialize fibonacci and time mvc
this.init();
}
/*
This Method should be "abstract"
Leave method as protected, as it is only authorized to extender of the class
Make new class that extends and defines init()
Inside references within this class would change from this to super
Repeat process using for, while, recursion
*/
protected void init() {
this.name = "Stream";
Stream.iterate(new long[]{0, 1}, f -> new long[]{f[1], f[0] + f[1]})
.limit(this.size)
.forEach(f -> this.setData(f[0]) );
}
/*
Number is added to fibonacci sequence, current state of "list" is added to hash for hashID "num"
*/
public void setData(long num) {
list.add(num);
hash.put(this.hashID++, list.clone());
}
/*
Custom Getter to return last element in fibonacci sequence
*/
public long getNth() {
return list.get(this.size - 1);
}
/*
Custom Getter to return last fibonacci sequence in HashMap
*/
public Object getNthSeq(int i) {
return hash.get(i);
}
/*
Console/Terminal supported print method
*/
public void print() {
System.out.println("Init method = " + this.name);
System.out.println("fibonacci Number " + this.size + " = " + this.getNth());
System.out.println("fibonacci List = " + this.list);
System.out.println("fibonacci Hashmap = " + this.hash);
for (int i=0 ; i<this.size; i++ ) {
System.out.println("fibonacci Sequence " + (i+1) + " = " + this.getNthSeq(i));
}
}
/*
Tester class method. If this becomes abstract you will not be able to test it directly ...
Change this method to call "main" class of each of the extended classes
*/
static public void main(String[] args) {
Fibo fib = new Fibo();
fib.print();
}
}
Fibo.main(null);
// While loop
public class FiboWhile extends Fibo {
public FiboWhile() {
this(10); // telescope to avoid code duplication, using default
}
public FiboWhile(int nth) {
this.size = nth;
this.list = new ArrayList<>();
this.hashID = 0;
this.hash = new HashMap<>();
//initialize fibonacci and time mvc
this.init();
}
static public void main(String[] args) {
FiboWhile wFib = new FiboWhile();
wFib.print();
}
// Custom init using while loop instead
protected void init() {
this.name = "While Loop";
int i = 0;
// new long array with only 0
long[] f = new long[] {0,1};
//while i is less than the length desired
while (i < this.size) {
// sets data first, then adds to f
this.setData(f[0]);
f = new long[] {f[1], f[0] + f[1]};
// adds to counter
i++;
}
}
}
FiboWhile.main(null)
// Recursion
public class FiboRecur extends Fibo {
public FiboRecur() {
this(10); // telescope to avoid code duplication, using default
}
public FiboRecur(int nth) {
this.size = nth;
this.list = new ArrayList<>();
this.hashID = 0;
this.hash = new HashMap<>();
//initialize fibonacci and time mvc
this.init();
}
static public void main(String[] args) {
FiboRecur rFib = new FiboRecur();
rFib.print();
}
// Recursion function, using int i as a counter
protected void recur(long[] f, int i) {
// Sets data using beginning value
this.setData(f[0]);
// Cretes new long
f = new long[]{f[1], f[0] + f[1]};
// Adds to counter
i++;
if (i < this.size) {
// Recusion continues if size limit has not been reached
this.recur(f, i);
}
}
// Custom init using recursion loop instead
protected void init() {
this.name = "Recursion";
// Uses int i as a counter for recusion, also creates initial long[]
int i = 0;
long[] f = new long[] {0,1};
// input long and counter i into recursion function
this.recur(f, i);
}
}
FiboRecur.main(null)
// For Loop
public class FiboFor extends Fibo {
public FiboFor() {
this(10); // telescope to avoid code duplication, using default
}
public FiboFor(int nth) {
this.size = nth;
this.list = new ArrayList<>();
this.hashID = 0;
this.hash = new HashMap<>();
//initialize fibonacci and time mvc
this.init();
}
static public void main(String[] args) {
FiboRecur rFib = new FiboRecur();
rFib.print();
}
// Custom init using for loop instead
protected void init() {
this.name = "For loop";
// creates initial long[]
long[] f = new long[] {0,1};
// iterates through until reaches desired length
for (int i = 0; i < this.size; i++) {
// sets data, then updates f
this.setData(f[0]);
f = new long[] {f[1], f[0] + f[1]};
}
}
}
FiboFor.main(null)