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public class  Rational 
{
private Int32 _inner_int = 0;
public Rational()
{
}
public Rational(Int32 num)
{
this._inner_int = num;
}
public Int32 ToInt32() { return this._inner_int; }
// Implicitly constructs and returns a Rational from an Int32
public static implicit operator Rational(Int32 num)
{
return new Rational(num);
}
// Explicitly returns an Int32 from a Rational
public static explicit operator Int32(Rational r)
{
return r.ToInt32();
}
public override string ToString()
{
//return base.ToString();
String s = String.Format("{0}"?? this._inner_int);
return s;
}
}

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class Program
{
static void Main(string[] args)
{
Rational r1 = 10;
Console.WriteLine(r1);
Int32 i = r1;
Console.WriteLine(i);
Console.ReadLine();
}
}

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