public static void SelectionSort <T>(T[] arr) where T : IComparable <T>
{
Debug.Assert(0 < arr.Length, "SelectionSort: Array cannot be empty!");
for (int index = 0; index < arr.Length - 1; index++)
{
int minElementIndex = FindMinElementIndex(arr, index, arr.Length - 1);
Swap(ref arr[index], ref arr[minElementIndex]);
}
bool isSorted = AssertionsHelpingFunctions.IsSortedArray(arr);
Debug.Assert(isSorted, "SelectionSort does not work correctly. Array is not sorted!");
}
private static int BinarySearch <T>(T[] arr, T value, int startIndex, int endIndex)
where T : IComparable <T>
{
Debug.Assert(0 < arr.Length, "BinarySearch: Array cannot be empty!");
Debug.Assert(value != null, "BinarySearch: Searched value cannot be null!");
Debug.Assert(0 <= startIndex && startIndex < arr.Length, "BinarySearch: Start index not in range!");
Debug.Assert(0 <= endIndex && endIndex < arr.Length, "BinarySearch: End index not in range!");
Debug.Assert(startIndex <= endIndex, "BinarySearch: Start index cannot be bigger than end index!");
bool isSortedArray = AssertionsHelpingFunctions.IsSortedArray(arr);
Debug.Assert(isSortedArray, "BinarySearch cannot be apply on unsorted array!");
while (startIndex <= endIndex)
{
int midIndex = (startIndex + endIndex) / 2;
if (arr[midIndex].Equals(value))
{
return(midIndex);
}
if (arr[midIndex].CompareTo(value) < 0)
{
// Search on the right half
startIndex = midIndex + 1;
}
else
{
// Search on the right half
endIndex = midIndex - 1;
}
}
bool hasValue = AssertionsHelpingFunctions.HasValue(arr, value);
Debug.Assert(hasValue, "BinarySearch returns -1, although searched value exist!");
// Searched value not found
return(-1);
}
private static int FindMinElementIndex <T>(T[] arr, int startIndex, int endIndex)
where T : IComparable <T>
{
Debug.Assert(0 < arr.Length, "FindMinElementIndex: Array cannot be empty!");
Debug.Assert(0 <= startIndex && startIndex < arr.Length - 1, "FindMinElementIndex: Start index not in range!");
Debug.Assert(0 < endIndex && endIndex < arr.Length, "FindMinElementIndex: End index not in range!");
Debug.Assert(startIndex < endIndex, "FindMinElementIndex: Start index cannot be bigger or equal than end index!");
int minElementIndex = startIndex;
for (int i = startIndex + 1; i <= endIndex; i++)
{
if (arr[i].CompareTo(arr[minElementIndex]) < 0)
{
minElementIndex = i;
}
}
bool isMinElementIndex = AssertionsHelpingFunctions.IsMinElementIndex(arr, minElementIndex);
Debug.Assert(isMinElementIndex, "FindMinElementIndex does not work correct. Invalid min element index!");
return(minElementIndex);
}
