Challenge 2 done

1 files changed, 63 insertions, 0 deletions

diff --git a/challenge-079/simon-proctor/raku/ch-2.raku b/challenge-079/simon-proctor/raku/ch-2.raku
new file mode 100644
index 0000000000..9824854e3a
--- /dev/null
+++ b/challenge-079/simon-proctor/raku/ch-2.raku
@@ -0,0 +1,63 @@
+#!/usr/bin/env raku
+
+use v6;
+
+my %*SUB-MAIN-OPTS = :named-anywhere;
+
+#| Given a list of height find the area of the largest single rectangle
+sub MAIN (
+    *@heights where { $_.all ~~ UInt && $_.elems >= 1 } , #= List of height
+) {
+    my @rain-levels =  calculate-rain-levels( @heights );
+    draw-heights( @heights, @rain-levels );
+    say [+] @rain-levels.map(*.area);
+}
+
+class RainArea {
+    has Range $.range;
+    has UInt $.height;
+    has UInt $.area;
+}
+
+sub draw-heights( @heights, @rain ) {
+    my $max = @heights.max;
+    my $width = $max.codes;
+    my $bar = '#' x $width;
+    my $spc = ' ' x $width;
+    my $dsh = '-' x $width;
+    my $wtr = '~' x $width;
+    my &spr = -> $x { sprintf( "%{$width}d", $x ) }
+    my &prt = -> $h {
+        -> $k, $v {
+            my @found = @rain.grep( -> $r { $k ~~ $r.range } );
+            if (@found && $h <= @found[0].height) {
+                $v >= $h ?? $bar !! $wtr;
+            } else {
+                $v >= $h ?? $bar !! $spc;
+            }
+        };
+    };
+    
+    for $max...1 -> $h {
+        my &fnc = &prt($h);
+        ( &spr( $h ),  |@heights.kv.map( &fnc ) ).join(" ").say;
+    }
+    ( $dsh xx @heights.elems + 1 ).join(" ").say;
+    ( $spc, |@heights.map( &spr ) ).join(" ").say;
+}
+
+multi sub calculate-rain-levels( @heights where { any(@heights[0^..^*-1]) > any(@heights[0],@heights[*-1]) }, $offset = 0) {
+    my $max = max(@heights[0^..^*-1]);
+    my $mid-idx = @heights[0^..^*-1].kv.map( -> $k, $v { $v == $max ?? $k+1 !! Empty } )[0];
+    
+    return ( |calculate-rain-levels( @heights[0..$mid-idx],$offset ), |calculate-rain-levels( @heights[$mid-idx..*],$mid-idx+$offset ) )
+}
+
+multi sub calculate-rain-levels( @heights where { @heights.elems > 2 }, $offset=0 ) {
+    my $height = min( @heights[0], @heights[*-1] );
+    my $area = $height * ( @heights.elems - 2 );
+    $area -= [+] @heights[0^..^*-1];
+    return RainArea.new( range => ( $offset..^($offset+@heights.elems) ), :$area, :$height ); 
+}
+
+multi sub calculate-rain-levels(@,$) {}