How to check if Array is sorted?

Question

How can I check if TArray is already sorted? I am using the default TArray.Sort to sort my array.

Answer 1

Check neighbour pairs with the same comparator as Sort uses

Result := True;
for i := Low(Arr) + 1 to High(Arr) do
  if Compare(Arr[i], Arr[i - 1]) < 0 then
    Exit(False);

It takes O(n) time (against O(nlogn) for sorting)