using System;
using System.Collections;
public class Starter {
public static void Main() {
SimpleCollection simple = new SimpleCollection(new object[] { 1, 2, 3, 4, 5, 6, 7 });
IEnumerator enumerator = simple.GetEnumerator();
while (enumerator.MoveNext()) {
Console.WriteLine(enumerator.Current);
}
}
}
public class SimpleCollection : IEnumerable {
public SimpleCollection(object[] array) {
items = array;
}
public IEnumerator GetEnumerator() {
return new Enumerator(items);
}
private object[] items = null;
}
public class Enumerator : IEnumerator {
public Enumerator(object[] items) {
elements = new object[items.Length];
Array.Copy(items, elements, items.Length);
cursor = -1;
}
public bool MoveNext() {
++cursor;
if (cursor > (elements.Length - 1)) {
return false;
}
return true;
}
public void Reset() {
cursor = -1;
}
public object Current {
get {
if (cursor > (elements.Length - 1)) {
throw new InvalidOperationException("Enumeration already finished");
}
if (cursor == -1) {
throw new InvalidOperationException(
"Enumeration not started");
}
return elements[cursor];
}
}
private int cursor;
private object[] elements = null;
}
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