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Task/Hailstone-sequence/Sidef/hailstone-sequence.sidef

@@ -0,0 +1,24 @@
+func hailstone (n) {
+    var sequence = [n];
+    while (n > 1) {
+        sequence.append(
+            n.is_even ? n.div!(2)
+                      : n.mul!(3).add!(1)
+        );
+    }
+    return(sequence);
+}
+
+# The hailstone sequence for the number 27
+var arr = hailstone(var nr = 27);
+say "#{nr}: #{arr.first(4).to_s} ... #{arr.last(4).to_s} (#{arr.len})";
+
+# The longest hailstone sequence for a number less than 100,000
+var h = [0, 0];
+99_999.times { |i|
+    (var l = hailstone(i).len) > h[1] && (
+        h = [i, l];
+    );
+}
+
+printf("%d: (%d)\n", h...);