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|
datatype t =
A of int ref * int
| B
val n = 100
val a = Array.tabulate (n, fn i =>
case i mod 3 of
0 => B
| 1 => A (ref 13, 14)
| 2 => A (ref 15, 16))
datatype t =
A' of int ref * int
| B'
val a' =
Array.tabulate (n, fn i =>
case Array.sub (a, i) of
B => B'
| A (r, n) => A' (r, n + 1))
val _ = Array.app (fn A (r, n) => r := 17 + n + !r | B => ()) a
val _ =
case Array.sub (a', 1) of
A' (r, n) => print (concat [Int.toString (!r + n), "\n"])
| B' => ()
|
