using System;

​

using System.Collections;

​

public class Sentence {

    protected string text;

    public Sentence(string t) {

        text = t;

    }

    public WordIterator GetIterator() {

        return new WordIterator(text);

    }

}

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public class WordIterator {

    int position = -1;

    public string text;

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    public WordIterator(string _text) {

        text = _text;

    }

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    public void Reset() {

        position = -1;

    }

    public string Next() {

​

​

    }

}

​

​

public class Program

{

    public static void Main()

    {

​

        Sentence s = new Sentence("hello world");

​

​

​

    }

}