Data update

Task/Digital-root/Gleam/digital-root.gleam

@@ -0,0 +1,49 @@
+import gleam/int
+import gleam/io
+import gleam/list
+
+pub fn sum_digits(n: Int) -> Int {
+  sum_digits_base(n, 10)
+}
+
+pub fn sum_digits_base(n: Int, base: Int) -> Int {
+  sum_digits_helper(n, base, 0)
+}
+
+fn sum_digits_helper(n: Int, base: Int, acc: Int) -> Int {
+  case n, base, acc {
+    0, _, acc -> acc
+    n, base, acc if n < base -> acc + n
+    n, base, acc -> sum_digits_helper(n / base, base, acc + { n % base })
+  }
+}
+
+pub fn persistance_root(x: Int) -> #(Int, Int) {
+  persistance_root_helper(sum_digits(x), 1)
+}
+
+fn persistance_root_helper(x: Int, n: Int) -> #(Int, Int) {
+  case x, n {
+    x, n if x < 10 -> #(n, x)
+    x, n -> persistance_root_helper(sum_digits(x), n + 1)
+  }
+}
+
+pub fn task() {
+  let ns = [627_615, 39_390, 588_225, 393_900_588_225]
+  let res = list.map(ns, fn(x) { #(x, persistance_root(x)) })
+  list.each(res, fn(pair) {
+    let #(x, #(y, z)) = pair
+    io.println(
+      x |> int.to_string
+      <> " has additive persitence "
+      <> y |> int.to_string
+      <> " and digital root of "
+      <> z |> int.to_string,
+    )
+  })
+}
+
+pub fn main() {
+  task()
+}