Data update

Task/Hailstone-sequence/SETL/hailstone-sequence.setl

@@ -0,0 +1,24 @@
+program hailstone_sequence;
+    hail27 := hailstone(27);
+    print("The hailstone sequence for the number 27 has", #hail27, "elements,");
+    print("starting with", hail27(..4), "and ending with", hail27(#hail27-3..));
+
+    sizes := [#hailstone(n) : n in [1..99999]];
+    maxsize := max/sizes;
+    maxelem := [n : n in [1..#sizes] | sizes(n) = maxsize](1);
+
+    print("The number < 100,000 with the longest hailstone sequence is",maxelem);
+    print("The length of its sequence is",sizes(maxelem));
+
+    proc hailstone(n);
+        seq := [];
+        loop doing seq with:= n; while n/=1 do
+            if even n then
+                n div:= 2;
+            else
+                n := 3*n + 1;
+            end if;
+        end loop;
+        return seq;
+    end proc;
+end program;