direct making adjacency-list

1 files changed, 8 insertions, 10 deletions

diff --git a/challenge-281/wambash/raku/ch-2.raku b/challenge-281/wambash/raku/ch-2.raku
index 85cbe99c8b..8a96934cd6 100644
--- a/challenge-281/wambash/raku/ch-2.raku
+++ b/challenge-281/wambash/raku/ch-2.raku
@@ -4,29 +4,27 @@ use Graph;
 
 
 enum Col (<a>..<h>);
-enum Row (1=> 1, slip 2..8);
+enum Row (1 => 1, slip 2..8);
 
 constant @vertices = Col::.values.sort X, Row::.values.sort;
 
 sub move ( @ (Col $col, Row $row), @ ($col-diff,$row-diff) ) {
-    try { Col($col+$col-diff), Row($row+$row-diff) }\
+    try { Col($col+$col-diff), Row($row+$row-diff) }\ 
     orelse Empty
 }
 
 sub knight-jump ( +@vertex (Col $, Row $) ) {
-     1 X, (-2, 2)
+    -1, 1  X,  -2, 2
     andthen .map: { slip $_, .reverse }\
     andthen .map: &move.assuming(@vertex)\
 }
 
-constant @edges = (
-    @vertices
-    andthen .map: { slip $_.join X, knight-jump $_  }\
-    andthen .map: { %( from => .[0].join, to => .[1].join, weight => 1 ) }
+constant %adjacency-list = %(
+    @vertices.map: { $_.join => set knight-jump($_).map: *.join  }\
 );
 
 constant knight-moves = Graph.new(
-    @edges
+    :%adjacency-list
 );
 
 sub knight's-move ($start, $end) {
@@ -36,8 +34,8 @@ sub knight's-move ($start, $end) {
 
 multi MAIN (Bool :test($)!) {
     use Test;
-    is knight-jump( g, Row(2) ), ((e,Row(3)),(h,Row(4)),);
-    is knight-jump( c, Row(4) ), ((d,Row(2)),(a,Row(5)),(d,Row(6)),(e,Row(5)));
+    is knight-jump( g, Row(2) ), ((e,Row(1)),(f,Row(4)),(e,Row(3)),(h,Row(4)),);
+    is knight-jump( c, Row(4) ), ((b,Row(2)),(a,Row(3)),(b,Row(6)),(e,Row(3)),(d,Row(2)),(a,Row(5)),(d,Row(6)),(e,Row(5)));
     is knight's-move('g2','a8'), 4;
     is knight's-move('g2','h2'), 3;
     is knight's-move('g2','h4'), 1;