using System;

public class Program

{

    public struct ShiftedIterator

    {

        public static ShiftedIterator Get(int aOffset, int aRange) => new ShiftedIterator(aOffset, aRange);

        int m_Offset, m_Index, m_Range;

        public ShiftedIterator GetEnumerator() => this;

        public int Current => (m_Index + m_Offset) % m_Range;

        public bool MoveNext() => ++m_Index < m_Range;

        public ShiftedIterator(int aOffset, int aRange)

        {

            m_Offset = (aOffset<0)?(aRange+aOffset%aRange):aOffset;

            m_Range = aRange;

            m_Index = -1;

        }

    }

    public static void Main()

    {

        Console.Write("Shifted by 4: ");

        foreach(var i in new ShiftedIterator(4,10))

            Console.Write(i+", ");

        Console.WriteLine();

        Console.Write("Shifted by -1: ");

        foreach(var i in new ShiftedIterator(-1,10))

            Console.Write(i+", ");

        Console.WriteLine();

        Console.Write("Shifted by -42: ");

        foreach(var i in ShiftedIterator.Get(-42,10))

            Console.Write(i+", ");

        Console.WriteLine();

    }

}