package com.qiusongde;

import java.util.Iterator;

import java.util.NoSuchElementException;

import edu.princeton.cs.algs4.StdIn;

import edu.princeton.cs.algs4.StdOut;

public class FixedCapacityStackOfStrings implements Iterable<String> {

    private String[] a;

    private int n;

    public FixedCapacityStackOfStrings(int cap) {

        a = new String[cap];

        n = 0;

    }

    public void push(String item) {

        if(isFull())

            throw new IndexOutOfBoundsException("FiexdCapcityStackOfString is Full");

        a[n++] = item;

    }

    public String pop() {

        if(isEmpty())

            throw new NoSuchElementException("FiexdCapcityStackOfString is empty");

        return a[--n];

    }

　　//1.3.1

    public boolean isFull() {

        return n == a.length;

    }

    public boolean isEmpty() {

        return n == 0;

    }

    public int size() {

        return n;

    }

    @Override

    public Iterator<String> iterator() {

        return new ReverseArrayIterator();

    }

    private class ReverseArrayIterator implements Iterator<String> {

        private int i = n;

        @Override

        public boolean hasNext() {

            return i > 0;

        }

        @Override

        public String next() {

            return a[--i];

        }

    }

    public static void main(String[] args) {

        int max = 5;

        FixedCapacityStackOfStrings stack = new FixedCapacityStackOfStrings(max);

        StdOut.println("stack initialized max size is:" + max);

        while (!StdIn.isEmpty()) {

            String item = StdIn.readString();

            if (!item.equals("-")) {

                if(stack.isFull())

                    StdOut.println("push error, stack full");

                else {

                    stack.push(item);

                    StdOut.println("push success:" + item + " size:" + stack.size());

                    StdOut.print("Left on stack: ");

                    for (String s : stack) {

                        StdOut.print(s + " ");

                    }

                    StdOut.println();

                }

            } else {

                if(stack.isEmpty())

                    StdOut.println("pop error, stack empty");

                else {

                    StdOut.println("pop success:" + stack.pop() + " size:" + stack.size());

                    StdOut.print("Left on stack: ");

                    for (String s : stack) {

                        StdOut.print(s + " ");

                    }

                    StdOut.println();

                }

            }

        }

    }

}

stack initialized max size is:5

to

push success:to size:1

Left on stack: to

be

push success:be size:2

Left on stack: be to

or

push success:or size:3

Left on stack: or be to

not

push success:not size:4

Left on stack: not or be to

to

push success:to size:5

Left on stack: to not or be to

be

push error, stack full

-

pop success:to size:4

Left on stack: not or be to

-

pop success:not size:3

Left on stack: or be to

-

pop success:or size:2

Left on stack: be to

-

pop success:be size:1

Left on stack: to

-

pop success:to size:0

Left on stack:

-

pop error, stack empty