Forward difference
editable example
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ghul
use IO.Std.write_line
use Collections
use Ghul.Pipes
differences(xs: List[int]) -> List[int] =>
zip(xs[1..<0], xs[0..<1])
|> map(((next, current)) => next - current)
|> collect_list()
forward(order: int, xs: List[int]) -> List[int] =>
if order == 0 then xs
else forward(order - 1, differences(xs))
fi
let xs: List[int] = [90, 47, 58, 29, 22, 32, 55, 5, 55, 73]
for order in 0..xs.count do
write_line("order {order}: {forward(order, xs) |> join(", ")}")
od