int *temp = (int *)malloc(sizeof(int)*array_size);
int mergeSort(int arr[], int temp[], int left, int right)
{
int count = 0;
if (right > left)
{
int mid = (right + left)/2;
count = mergeSort(arr, temp, left, mid);
count += mergeSort(arr, temp, mid+1, right);
count += merge(arr, temp, left, mid, right);
}
return count;
}
int merge(int arr[], int temp[], int left, int mid, int right)
{
int i, j, k;
int count1 = 0;
i = left;
j = mid+1;
k = left;
while ((i <= mid) && (j <= right))
{
if (arr[i] <= arr[j])
{
temp[k++] = arr[i++];
}
else
{
temp[k++] = arr[j++];
count1 += (mid - i);
}
}
while (i <= mid)
temp[k++] = arr[i++];
while (j <= right)
temp[k++] = arr[j++];
for (i=left; i <= right; i++)
arr[i] = temp[i];
}