Searching.cs

using System.Diagnostics;

namespace Arrays;

public class Searching
{
    public static void SearchWithIndexOf(string[] myRecentFiles, string openedFile)
    {
        int recentFileListIndex = Array.IndexOf(myRecentFiles, openedFile);
        if (recentFileListIndex < 0)
        {
            AddNewRecentEntry(openedFile);
        }
        else
        {
            MoveExistingRecentEntryToTop(recentFileListIndex);
        }
    }

    public static int GetIndexOfFirstNonEmptyBin(int[] bins)
        => Array.FindIndex(bins, IsNonZero);

    private static bool IsNonZero(int value) => value != 0;

    public class WithLambda
    {
        public static int GetIndexOfFirstNonEmptyBin(int[] bins)
            => Array.FindIndex(bins, value => value != 0);
    }

    public static T[] GetNonNullItems<T>(T[] items) where T : class
        => Array.FindAll(items, value => value != null);

    public static void SearchPerf()
    {
        var sw = new Stopwatch();

        int[] big = new int[100_000_000];
        Console.WriteLine("Initializing");
        sw.Start();
        var r = new Random(0);
        for (int i = 0; i < big.Length; ++i)
        {
            big[i] = r.Next(big.Length);
        }
        sw.Stop();
        Console.WriteLine(sw.Elapsed.ToString("s\\.f"));
        Console.WriteLine();

        Console.WriteLine("Searching");
        for (int i = 0; i < 6; ++i)
        {
            int searchFor = r.Next(big.Length);
            sw.Reset();
            sw.Start();
            int index = Array.IndexOf(big, searchFor);
            sw.Stop();
            Console.WriteLine($"Index: {index}");
            Console.WriteLine($"Time:  {sw.Elapsed:s\\.ffff}");
        }
        Console.WriteLine();

        Console.WriteLine("Sorting");
        sw.Reset();
        sw.Start();
        Sort(big);
        sw.Stop();
        Console.WriteLine(sw.Elapsed.ToString("s\\.ff"));
        Console.WriteLine();

        Console.WriteLine("Searching (binary)");
        for (int i = 0; i < 6; ++i)
        {
            int searchFor = r.Next() % big.Length;
            sw.Reset();
            sw.Start();
            int index = Find(big, searchFor);
            sw.Stop();
            Console.WriteLine($"Index: {index}");
            Console.WriteLine($"Time:  {sw.Elapsed:s\\.fffffff}");
        }

        void Sort(int[] numbers)
        {
            Array.Sort(numbers);
        }

        int Find(int[] numbers, int searchFor)
        {
            return Array.BinarySearch(numbers, searchFor);
        }
    }

    private static void MoveExistingRecentEntryToTop(int recentFileListIndex)
    {
    }

    private static void AddNewRecentEntry(string openedFile)
    {
    }
}