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68
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1 package fschmidt.util.java;
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2
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3 import java.util.Collection;
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4 import java.util.List;
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5 import java.util.ArrayList;
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6 import java.util.EmptyStackException;
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7
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8
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9 public class ArrayStack<E> extends ArrayList<E> implements Stack<E> {
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10
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11 public ArrayStack() {}
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12
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13 public ArrayStack(Collection<E> c) {
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14 super(c);
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15 }
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16
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17 @Override public void push(E item) {
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18 add(item);
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19 }
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20
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21 @Override public E pop() throws EmptyStackException {
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22 int len = size();
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23 if (len == 0)
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24 throw new EmptyStackException();
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25 return remove(len - 1);
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26 }
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27
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28 @Override public E peek() throws EmptyStackException {
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29 int len = size();
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30 if (len == 0)
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31 throw new EmptyStackException();
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32 return get(len - 1);
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33 }
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34
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35 }
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