using System;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var binaryInput = "1010101";

​

        var shifts = 1;

        while (binaryInput != string.Join("", binaryInput.TakeLast(shifts).Concat(binaryInput.SkipLast(shifts))))

        {

            shifts++;

        }

​

        Console.WriteLine(shifts);

    }

}