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+#!/usr/bin/env raku
+# :vim ft=raku sw=4 expandtab  # 🦋 ∅∪∩∋∈∉ ≡ ≢ «␤ » ∴
+use v6.d;
+use Test;
+
+=begin comment
+241-2: Prime Order              Submitted by: Mohammad S Anwar
+Given an array of unique positive integers greater than 2, sort them in
+ascending order of the count of their prime factors, tie-breaking by ascending
+value.
+
+Example 1
+Input: @int = (11, 8, 27, 4)
+Output: (11, 4, 8, 27))
+
+Prime factors of 11 => 11
+Prime factors of  4 => 2, 2
+Prime factors of  8 => 2, 2, 2
+Prime factors of 27 => 3, 3, 3
+=end comment
+
+my @Test =
+    [11,8,27,4], [11,4,8,27],
+    [8,27], [8,27],
+    [27,8], [8,27],
+;
+
+plan @Test ÷ 2;
+
+subset Positive of Int where * ≥ 1;
+
+constant @prime = lazy 2,3, (* + 2 if *.is-prime) … ∞;
+
+sub prime-factors( $n is copy -->Array) is export {
+    my @ret;
+    my $ix = 0;
+    while $n > 1 {
+        my $candi = @prime[$ix];
+        $ix++;
+        next unless ( $n %% $candi );
+        $ix = 0;
+        $n ÷= $candi;
+        @ret.push: $candi;
+    }
+    return @ret;
+}
+
+sub sort-by-prime-factor-ct-then-val( @a) {
+    @a.sort: { .&prime-factors.elems, $_  };
+}
+
+for @Test -> @in, @exp {
+    is sort-by-prime-factor-ct-then-val(@in), @exp, "@in.raku() -> @exp.raku()";
+}
+
+done-testing;
+
+my @a = 11, 2³, 3³, 2², 3, 97, 3²×11, 2²×5², 2³x3²×7×17×37, 2⁹;
+say "Input: @int = @a.raku()\nOutput: &sort-by-prime-factor-ct-then-val( @a)";
+
+exit;
+