How to shift the start of an array in C#?

Question

I\'m trying to reorganize an array based on the first occurrence of a value (thus simulating similar functionality to a circular array.)

For example, in the followin

Answer 1

As an alternative to creating a new array, you can wrap it with a class:

class CircularList<T> : IList<T>
{
    static IEnumerable<T> ToEnumerator(CircularList<T> list)
    {
        for (int i = 0; i < list.Count; i++)
        {
            yield return list[i];
        }
    }

    IList<T> arr;
    public int Shift { get; private set; }
    public CircularList(IList<T> arr, int shift)
    {
        this.arr = arr;
        this.Shift = shift;
    }

    int shiftIndex(int baseIndex)
    {
        return (baseIndex + Shift) % arr.Count;
    }

    #region IList<T> Members

    public int IndexOf(T item) { throw new NotImplementedException(); }
    public void Insert(int index, T item) { throw new NotImplementedException(); }
    public void RemoveAt(int index) { throw new NotImplementedException(); }
    public T this[int index]
    {
        get { return arr[shiftIndex(index)]; }
        set { arr[shiftIndex(index)] = value; }
    }

    #endregion

    #region ICollection<T> Members

    public void Add(T item) { throw new NotImplementedException(); }
    public void Clear() { throw new NotImplementedException(); }
    public bool Contains(T item) { throw new NotImplementedException(); }
    public void CopyTo(T[] array, int arrayIndex) { throw new NotImplementedException(); }
    public int Count { get { return arr.Count; } }
    public bool IsReadOnly { get { throw new NotImplementedException(); } }
    public bool Remove(T item) { throw new NotImplementedException(); }

    #endregion

    #region IEnumerable<T> Members

    public IEnumerator<T> GetEnumerator()
    {
        return ToEnumerator(this).GetEnumerator();
    }

    #endregion

    #region IEnumerable Members

    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        return ToEnumerator(this).GetEnumerator();
    }

    #endregion
}

This program:

class Program
{
    static void Main(string[] args)
    {
        int[] myArray = { 2, 3, 6, 1, 7, 6 };
        CircularList<int> circularList =
            new CircularList<int>(myArray, Array.IndexOf<int>(myArray, 6));

        foreach (int i in circularList)
        {
            Console.WriteLine(i);
        }
    }
}

Prints the following:

6
1
7
6
2
3

Answer 2

C# answer: input : { 1, 2, 3, 5, 6, 7, 8 }; Output : { 8, 7 1, 2, 3, 5, 6};

{
    static void Main(string[] args)
    {
        int[] array = { 1, 2, 3, 5, 6, 7, 8 };
        int index = 2;
        int[] tempArray = new int[array.Length];
        array.CopyTo(tempArray, 0);

        for (int i = 0; i < array.Length - index; i++)
        {
            array[index + i] = tempArray[i];
        }

        for (int i = 0; i < index; i++)
        {
            array[i] = tempArray[array.Length -1 - i];
        }            


    }
}