,QWHUID]SDUDSLODVcdk/curs/prog2/00-01/pilas-colas2.pdf · 3 Copyright © 2001 [email protected] Java:...

$: ,QWHUID]SDUDSLODVcdk/curs/prog2/00-01/pilas-colas2.pdf · 3 Copyright © 2001 cdk@it.uc3m.es Java: Pilas y Colas / 5,PSOHPHQWDFLyQ EDVDGDHQDUUD\V public int size() {return (top+1);}$
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Copyright © 2001 [email protected] Java: Pilas y Colas / 1

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public interface Stack {

public int size();

public boolean isEmpty();

public void push(Object o);

public Object pop()throws StackEmptyException;

public Object top()throws StackEmptyException;

}


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Stack

LinkedStack

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public class ArrayStack implements Stack {

public static final int CAP=1000;

private int capacity;

private Object S[];

private int top=-1;

public ArrayStack(){this(CAP);}

public ArrayStack(int cap){capacity=cap;

S=new Object[capacity];}

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public int size(){return (top+1);}

public boolean isEmpty(){return (top<0);}

public Object top()throws StackEmptyException {

if (isEmpty())

throw new StackEmptyException("vacio"};

return S[top];}


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public void push(Object o)throws StackFullException {if (size()==capacity)

throw new StackFullException("lleno");

S[++top]=o;}

public Object pop()throws StackEmptyException {

Object el;

if (isEmpty())throw new StackEmptyException("vacio"};

el=S[top]; S[top--]=null; return el;}

}

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class Node {private Object elem;

private Node next;

public Node(Object e, Node n) {elem=e; next=n;}

void setElem(Object e) {elem=e;}

void setNext(Node n) {next=n;}

Object getElem() {return elem;}

Node getNext() {return next;}}

5


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public class LinkedStack implements Stack {

private Node top;

private int size;

public LinkedStack() {top=null; size=0;}

public int size() {return size;}

public boolean isEmpty() {return(top==null);}


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public void push(Object e) {

Node n=New Node();

n.setElem(e);

n.setNext(top);

top=n;

size++;

}

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public Object top()

throws StackEmptyException {

if (isEmpty())

throw new StackEmptyException("vacia");

return top.getElem();

}

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public Object pop()throws StackEmptyException {

Object temp;

if (isEmpty())

throw new StackEmptyException("vacia");

temp=top.getElem();top=top.getNext();

size--;

return temp;

}


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❚ public static long fac (int n){if (n<=1)

return 1;else

return n*fac(n-1);}


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❚ fac(4)

❚ 4*fac(3)

❚ 4*(3*fac(2))

❚ 4*(3*(2*fac(1)))

❚ 4*(3*(2*1)))

❚ 4*(3*2)

❚ 4*6

❚ 24

2*

3*4*

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public interface Queue {

public int size();

public boolean isEmpty();

public void enqueue(Object o);

public Object dequeue()throws QueueEmptyException;

public Object front()throws QueueEmptyException;

}

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ArrayQueue

Queue

LinkedQueue


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public void enqueue(Object e) {Node n=New Node();

n.setElem(e);

n.setNext(null);

if (size==0)

top=n;else

tail.setNext(n);

tail=n;

size++;}


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public Object dequeue()throws QueueEmptyException {

Object temp;

if (isEmpty())

throw new QueueEmptyException("vacia");

temp=top.getElem();top=top.getNext();

size--;

if (size==0)

tail=nullreturn temp;

}

,QWHUID]SDUDSLODVcdk/curs/prog2/00-01/pilas-colas2.pdf · 3 Copyright © 2001 [email protected] Java:...

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