Find the unique value in an array

Question

a non o' mouse · Accepted Answer

Example: 

            while (start  Check for equal to target value
   /     \
(1)      (3)
 |          |
 |          ----> start = (this leaf index) : if target is > parent
 |
 ----> end = (this leaf index) : if target =. Use index 8 and 3 in the array above as two prime examples. Furthermore, it would take a stroke of luck to find the unique value "1"

take this for example:

You have a struct named MyStruct with members ID which is type int and Value which is type int. If you randomly generated 'n' number of these and all except one were duplicates, how would you find the unique value?

a non o' mouse · Answer

public struct MyStruct : IEquatable, IComparable
    { 
        // Saved for the sake of not having to recalculate every time its called (Specifically for this example.)
        private int _hashCode;

        public MyStruct(int id, int value)
        {
            ID = id;
            Value = value;
            _hashCode = 0;
        }

        public int ID { get; }
        public int Value { get; }

        public int CompareTo(MyStruct other)
        {
            return GetHashCode() == other.GetHashCode() ? 0 : GetHashCode() (MyStruct a, MyStruct b)
        {
            return a.GetHashCode() > b.GetHashCode();
        }

        public static bool operator  {Value}";
        }

        public override bool Equals(object obj)
        {
            return obj is MyStruct && obj.GetHashCode() == GetHashCode();
        }

        #endregion
    }

a non o' mouse · Answer

internal class Program
    {
        private static void Main(string[] args)
        {
            // Create a unique value
            var unique = new MyStruct("Unique".GetHashCode(), 0x200);

            // Prepare for all test cases
            var executionArray = new Func[]
            {
                executeFindCustomStructWithLinq,
                executeFindUniqueWithHashSet,
                executeFindUniqueWithBinaryTree
            };

            // Execute test cases and get results
            var resultsTypeArray = executionArray.Select( method => new {Name = nameof(method), Result = method(unique)});

            // print the results from the case
            resultsTypeArray.ToList().ForEach(item => WriteResults(item.Name,unique,item.Result));
            Console.ReadKey();
        }

        private static void WriteResults(string methodName, MyStruct orig, MyStruct target)
        {
            Console.WriteLine($"{methodName}: {orig} == {target}");
        }

        private static IList CreateDataSet(MyStruct unique)
        {
            var random = new Random();
            var amount = random.Next(0X0, 0x100);
            var myStructFactory = MyStructFactory.Instance;

            var dataSet = new List((amount*2) + 1);
            dataSet.AddRange(myStructFactory.Create(amount));

            // create a copy of the base data set
            var holdingBuffer = new MyStruct[dataSet.Count];
            dataSet.CopyTo(holdingBuffer, 0);

            // Insert Unique somewhere in the set
            dataSet.Insert(random.Next(0, dataSet.Count), unique);

            // add duplicated base dataset
            dataSet.AddRange(holdingBuffer);
            return dataSet;
        }

        #region ExecutionExamples

        private static MyStruct executeFindUniqueWithBinaryTree(MyStruct unique)
        {
            // Keep in mind this would only work if we knew the value before trying to parse the data set.
            var dataSet = CreateDataSet(unique);

            var orderedDataSet = dataSet.OrderBy(@struct => @struct).ToArray();
            var start = 0;
            var identifiedUnique = new MyStruct();
            var end = orderedDataSet.Count();

            while (start ();
            var identifiedUnique = new MyStruct();

            for (var i = 0; i  a ^= b);
            return identifiedUnique;
        }

        #endregion
    }

a non o' mouse · Answer

internal class MyStructFactory
    {
        internal const int CharMin = 0x20;
        internal const int CharMax = 0x7f;
        private readonly Random _random = new Random();

        static MyStructFactory()
        {
            Instance = new MyStructFactory();
        }

        private MyStructFactory()
        {
        }

        public static MyStructFactory Instance { get; }

        public MyStruct Create()
        {
            return new MyStruct(CreateName().GetHashCode(), CreateValue());
        }

        public IEnumerable Create(int amount)
        {
            return Enumerable.Range(0, amount).Select(i => Create());
        }

        private string CreateName()
        {
            var name = new char[_random.Next(0x4, 0xa)];
            for (var i = 0; i < name.Length; i++)
            {
                name[i] = (char) _random.Next(CharMin, CharMax);
            }
            return new string(name);
        }

        private int CreateValue()
        {
            return _random.Next(0x80, 0x100);
        }
    }

a non o' mouse · Answer

Edit:

3. HashSet implemented solution:
            Your code fails to successfully complete the task. Your output is similar to "0,1,2,3,4,5". As you can see, your implementation did not pull the unique values out of the array, but only executed as (remove { Distinct }) (add { HashSet }) was designed to, it removed the duplicate values.

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