ch-2.p6 simplified

1 files changed, 6 insertions, 9 deletions

diff --git a/challenge-089/mark-anderson/raku/ch-2.p6 b/challenge-089/mark-anderson/raku/ch-2.p6
index 47c7b8292b..c698059b65 100644
--- a/challenge-089/mark-anderson/raku/ch-2.p6
+++ b/challenge-089/mark-anderson/raku/ch-2.p6
@@ -9,16 +9,13 @@ unit sub MAIN(UInt $n where * mod 2 = 3); #= a positive odd integer
 .say for odd-magic-square($n);
 
 sub odd-magic-square($n) {
-    subset Valid of UInt where 0 <= * < $n;
-
-    my $r := Scalar::History.create(0, Valid);
-    my $c := Scalar::History.create(($n / 2).floor, Valid); 
     my @matrix = [0 xx $n] xx $n;
-    @matrix[$r][$c] = 1; 
+    my $r := Scalar::History.create(1);
+    my $c := Scalar::History.create(($n / 2).floor - 1); 
 
-    for 2..($n**2) -> $num {
-        try $r--; if $! { $r = $n - 1 }
-        try $c++; if $! { $c = 0      } 
+    for 1..($n**2) -> $num {
+        $r = ($r - 1) mod $n;
+        $c = ($c + 1) mod $n;
 
         if @matrix[$r][$c] {
             $r = $r.VAR.get-history.tail + 1;
@@ -28,5 +25,5 @@ sub odd-magic-square($n) {
         @matrix[$r][$c] = $num;
     }
 
-    @matrix.map(*.fmt("%{($n**2).chars}d").Array);
+    @matrix.map(*.fmt( "%{ ($n**2).chars }d" ).Array);
 }