public static void SelectionSort <T>(T[] arr)
where T : IComparable <T>
{
Debug.Assert(arr != null, "The array doesn't exist");
bool elementOfArrIsNull = AssertionHelpers.CheckArrayForNullElement(arr);
Debug.Assert(elementOfArrIsNull, "At least one element of 'arr' is null");
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 = AssertionHelpers.ValidateSorting(arr);
Debug.Assert(isSorted, "Sorting failed.");
}
private static int BinarySearch <T>(T[] arr, T value, int startIndex, int endIndex)
where T : IComparable <T>
{
int len = arr.Length;
Debug.Assert(len >= startIndex, "startIndex is out of range.");
Debug.Assert(len >= endIndex, "endIndex is out of range.");
Debug.Assert(startIndex < endIndex, "endIndex is out of range.");
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 arrayContainsValue = AssertionHelpers.CheckArrayForValue(arr, value);
Debug.Assert(!arrayContainsValue, "Invalid return reached. The element exists in the array!");
// Searched value not found
return(-1);
}
private static int FindMinElementIndex <T>(T[] arr, int startIndex, int endIndex)
where T : IComparable <T>
{
int len = arr.Length;
Debug.Assert(len >= startIndex, "startIndex is out of range.");
Debug.Assert(len >= endIndex, "endIndex is out of range.");
Debug.Assert(startIndex < endIndex, "endIndex is out of range.");
int minElementIndex = startIndex;
for (int i = startIndex + 1; i <= endIndex; i++)
{
if (arr[i].CompareTo(arr[minElementIndex]) < 0)
{
minElementIndex = i;
}
}
bool isMinElementIndex = AssertionHelpers.ValidateMinElementIndex(arr, minElementIndex, startIndex, endIndex);
Debug.Assert(isMinElementIndex, "minElementIndex is not the index of the minimum element.");
return(minElementIndex);
}
