Data update

Task/Additive-primes/Rebol/additive-primes.rebol

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+Rebol [
+    title: "Rosetta code: Additive primes"
+    file:  %Additive_primes.r3
+    url:   https://rosettacode.org/wiki/Additive_primes
+    note:  "Based on Red language solution"
+]
+primes: function [n [integer!]][
+    ;; See: https://rosettacode.org/wiki/Sieve_of_Eratosthenes#Rebol
+    poke prim: make bitset! n 1 true
+    r: 2 while [r * r <= n][repeat q n / r - 1 [poke prim q + 1 * r true]
+    until [not pick prim r: r + 1]]
+    collect [repeat i n [unless prim/:i [keep i]]]
+]
+;; Compute the digit sum (cross-sum) of an integer n
+cross-sum: function [n][
+    out: 0                 ;; accumulator for sum of digits
+    foreach m form n [     ;; iterate over the characters of n's string form
+        out: out - 48 + m  ;; convert char to integer, add to out
+    ]
+    out
+]
+;; Return all additive primes <= n:
+;; A prime p is "additive" if its digit-sum is also prime.
+additive-primes: function [n][
+    collect [
+        foreach p ps: primes n [       ;; generate primes up to n and iterate over them
+            if find ps cross-sum p [   ;; check if digit-sum of p is itself in the prime set
+                keep p                 ;; keep p if digit-sum is prime
+            ]
+        ]
+    ]
+]
+
+;; Generate additive primes up to 500
+result: additive-primes 500
+;; Format nicely by rows of 10 (with newlines)
+print [length? result "additive primes < 500:"]
+forall result [
+    prin pad result/1 -4
+    if zero? ((index? result) % 10) [print ""]
+]
+print ""