Data commit

Task/Hailstone-sequence/S-lang/hailstone-sequence.slang

@@ -0,0 +1,45 @@
+% lst=1, return list of elements; lst=0 just return length
+define hailstone(n, lst)
+{
+  variable l;
+  if (lst) l = {n};
+  else l = 1;
+
+  while (n > 1) {
+    if (n mod 2)
+      n = 3 * n + 1;
+    else
+      n /= 2;
+    if (lst)
+      list_append(l, n);
+    else
+      l++;
+    % if (prn) () = printf("%d, ", n);
+  }
+  % if (prn) () = printf("\n");
+  return l;
+}
+
+variable har = list_to_array(hailstone(27, 1)), more = 0;
+() = printf("Hailstone(27) has %d elements starting with:\n\t", length(har));
+
+foreach $1 (har[[0:3]])
+  () = printf("%d, ", $1);
+
+() = printf("\nand ending with:\n\t");
+foreach $1 (har[[length(har)-4:]]) {
+  if (more) () = printf(", ");
+  more = printf("%d", $1);
+}
+
+() = printf("\ncalculating...\r");
+variable longest, longlen = 0, h;
+_for $1 (2, 99999, 1) {
+  $2 = hailstone($1, 0);
+  if ($2 > longlen) {
+    longest = $1;
+    longlen = $2;
+    () = printf("longest sequence started w/%d and had %d elements  \r", longest, longlen);
+  }
+}
+() = printf("\n");