Complex1

using System;

namespace ConsoleApp1
{
    public static class NumberFinder
    {
        public static bool BinaryNumberSearch(this int[] numbers, int findNumber)
        {
            var left = 0;
            var right = numbers.Length - 1;

            while (left < right)
            {
                var middle = (left + right) / 2;
                if (findNumber <= numbers[middle])
                    right = middle;
                else
                    left = middle + 1;
            }
            if (numbers[right] == findNumber)
                return true;
            return false;
        }
    }

    class Program
    {
        static void Main()
        {
            var leftBorder = int.Parse(Console.ReadLine());
            var rightBorder = int.Parse(Console.ReadLine());
            var findNumber = int.Parse(Console.ReadLine());

            int[] numbers = new int[] { 1, 5, 6, 3, 2, 2, -10};
            int[] intervalNumbers = new int[rightBorder - leftBorder + 1];
            Array.Copy(numbers, leftBorder, intervalNumbers, 0, intervalNumbers.Length);
            Array.Sort(intervalNumbers);
            Console.WriteLine(intervalNumbers.BinaryNumberSearch(findNumber));
        }
    }
}