//Part 1 : CountInversion() *Split*
public static int CountInversion(List <int> numbers)
{
//base case
if (numbers.Count == 1)
{
return(0);
}
//creat int midle , list left and right .
var mid = numbers.Count / 2;
var left = new List <int> ();
var right = new List <int> ();
//left is input list until midle and right is numbers after midle .
left = SplitLeft(numbers, left, mid);
right = SplitRight(numbers, right, mid);
//Initialize int counter that equle CountInversion(left) + CountInversion(right).
var counter = CountInversion(left) + CountInversion(right);
//sort left and right .
left = MergeSorter.MergeSort(left.ToArray()).ToList();
right = MergeSorter.MergeSort(right.ToArray()).ToList();
// return count(left , right , counter).
return(Count(left, right, counter));
}
public static List <int> RandomSortedList()
{
var numbers = new List <int> ();
var x = new Random().Next(4, 10);
for (int i = 0; i <= x; i++)
{
numbers.Add(new Random().Next(0, 100));
}
return(MergeSorter.MergeSort(numbers.ToArray()).ToList());
}
//**********************************************
// Test Q9 merge sort
//***********************************************
public static bool TestMergeSoet()
{
var x = RandomIntArray();
x = MergeSorter.MergeSort(x);
for (int i = x.Length - 1; i > 0; i--)
{
if (x[i] < x[i - 1])
{
return(false);
}
}
return(true);
}
public static bool TestInversionsTwo()
{
var numbers = RandomIntArray().ToList();
numbers = MergeSorter.MergeSort(numbers.ToArray()).ToList();
var x = new Random().Next(1, 5);
var y = new Random().Next(6, 10);
var counter = 0;
if (counter == Inversions.NumberOfInversions(numbers))
{
return(true);
}
else
{
return(false);
}
}
//****************************************************************
//Test Q10 Inversions
//****************************************************************
public static bool TestInversions()
{
var numbers = RandomIntArray().ToList();
numbers = MergeSorter.MergeSort(numbers.ToArray()).ToList();
var i = new Random().Next(1, 20);
var x = numbers[0];
numbers[i] = numbers[0];
numbers[0] = x;
if (Inversions.NumberOfInversions(numbers) == i - 1)
{
return(true);
}
else
{
return(false);
}
}
