Data commit

Task/Hailstone-sequence/Bracmat/hailstone-sequence.bracmat

@@ -0,0 +1,43 @@
+(
+  ( hailstone
+  =   L len
+    .   !arg:?L
+      &   whl
+        ' ( !arg:~1
+          & (!arg*1/2:~/|3*!arg+1):?arg
+          & !arg !L:?L
+          )
+      & (!L:? [?len&!len.!L)
+  )
+& ( reverse
+  =   L e
+    .   :?L
+      & whl'(!arg:%?e ?arg&!e !L:?L)
+      & !L
+  )
+& hailstone$27:(?len.?list)
+& reverse$!list:?first4 [4 ? [-5 ?last4
+& put$"Hailstone sequence starting with "
+& put$!first4
+& put$(str$(" has " !len " elements and ends with "))
+& put$(!last4 \n)
+& 1:?N
+& 0:?max:?Nmax
+&   whl
+  ' ( !N+1:<100000:?N
+    &   hailstone$!N
+      : (   >!max:?max&!N:?Nmax
+          | ?
+        . ?
+        )
+    )
+&   out
+  $ ( str
+    $ ( "The number <100000 with the longest hailstone sequence is "
+        !Nmax
+        " with "
+        !max
+        " elements."
+      )
+    )
+);