// pages 55 through top of 57

using System;
using System.Collections;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;
using System.IO;

namespace csharp
{
    class chapter4
    {
        static int SeqSearch(int[] arr, int sValue)
        {
            for (int index = 0; index < arr.Length; index++)
            {
                if (arr[index] == sValue)
                    return index;
            }
            return -1;
        }

        static void Main(string[] args)
        {
            int[] numbers = new int[100];
            StreamReader numFile = File.OpenText("numbers.txt");
            for (int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = Convert.ToInt32(numFile.ReadLine(), 10);
            }
            int searchNumber;
            Console.Write("Enter a number to search for: ");
            searchNumber = Convert.ToInt32(Console.ReadLine(), 10);
            int foundAt;
            found = SeqSearch(numbers, searchNumber);
            if (foundAt >= 0)
                Console.WriteLine(searchNumber + " is in the array at position " + foundAt + ".");
            else
                Console.WriteLine(searchNumber + " is not in the array.");
			Console.Write(numbers[0] + " ");
			for(int i = 1; i < numbers.Length; i++) {
				if (i % 10 == 0)
					Console.WriteLine();
				Console.Write(numbers[i] + " ");
			}
            Console.ReadKey();
        }
    }
}

// FindMin and FindMax page 59

        static int FindMin(int[] arr)
        {
            int min = arr[0];
            for (int i = 0; i < arr.Length - 1; i++)
            {
                if (arr[i] < min)
                    min = arr[i];
            }
            return min;
        }

        static int FindMax(int[] arr)
        {
            int max = arr[0];
            for (int i = 0; i < arr.Length - 1; i++)
            {
                if (arr[i] > max)
                    max = arr[i];
            }
            return max;
        }

// page 60

 static void swap(int[] arr, int index)
 {
    int temp = arr[0];
    arr[0] = arr[index];
    arr[index] = temp;
 }

static bool SeqSearch(int[] arr, int sValue)
{
   for (int index = 0; index < arr.Length - 1; index++)
   {
      if (arr[index] == sValue)
      {
         swap(arr, index);
         return true;
      }
   }
   return false;
}

// page 61

static int SeqSearch(int[] arr, int sValue)
{
   for (int index = 0; index < arr.Length - 1; index++)
   {
      if (arr[index] == sValue && index > (arr.Length * .2))
      {
         swap(arr, index);
         return index;
      }
      else
         if (arr[index] == sValue)
            return index;
   }
   return -1;
}

// pp. 63 and 64 - put the function in the CArray class from chapter 3
// and use the following driver program

public int binSearch(int value)
{
   int upperBound, lowerBound, mid;
   upperBound = arr.Length - 1;
   lowerBound = 0;
   while (lowerBound <= upperBound)
   {
      mid = (upperBound + lowerBound) / 2;
      if (arr[mid] == value)
         return mid;
      else if (value < arr[mid])
         upperBound = mid - 1;
      else
         lowerBound = mid + 1;
   }
   return -1;
}
     

static void Main(string[] args)
{
   CArray nums = new CArray(10);
   Random rnd = new Random(100);
   for(int i = 0; i <= 9; i++)
       nums.Insert(rnd.Next(1,100));
   nums.BubbleSort();
   nums.DisplayElements();
   Console.Write("Enter a number to search for: ");
   int number = Convert.ToInt32(Console.ReadLine());
   int index = nums.binSearch(number);
   Console.WriteLine("Index value of searched value: " + index);
   Console.ReadKey();
}

// page 65

public int RbinSearch(int value, int lower, int upper)
{
   if (lower > upper)
      return -1;
   else
   {
      int mid;
      mid = (int)(upper + lower) / 2;
      if (value < arr[mid])
         return RbinSearch(value, lower, mid - 1);
      else if (value == arr[mid])
         return mid;
      else
         return RbinSearch(value, mid + 1, upper);
   }
}