From 5e69fb37abe78e1d6e9f6f747f3ecf391d2492cf Mon Sep 17 00:00:00 2001
From: Andrew Shitov <andy@shitov.ru>
Date: Wed, 23 Sep 2020 09:56:30 +0200
Subject: ash 079-2

---
 challenge-079/ash/raku/ch-2.raku | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 challenge-079/ash/raku/ch-2.raku

diff --git a/challenge-079/ash/raku/ch-2.raku b/challenge-079/ash/raku/ch-2.raku
new file mode 100644
index 0000000000..d04ce7a257
--- /dev/null
+++ b/challenge-079/ash/raku/ch-2.raku
@@ -0,0 +1,32 @@
+#!/usr/bin/env raku
+#
+# Task 2 from
+# https://perlweeklychallenge.org/blog/perl-weekly-challenge-079/
+
+my @shape = 2, 1, 4, 1, 2, 5;
+
+# Make the matrix and fill it with '#' (bricks) and '~' (water);
+my $height = max(@shape);
+my @map;
+for @shape -> $cell {
+    push @map, Array.new(('#' xx $cell, '~' xx ($height - $cell)).flat);
+}
+
+blow-water-out(0, @shape.end);
+blow-water-out(@shape.end, 0);
+
+.join.say for @map;
+
+# Units of water left
+say @map.join.join.indices('~').elems;
+
+sub blow-water-out($from, $to) {
+    # Blow from left or from right to remove high waters.
+    my $max = @shape[$from]; # Height of the left-most (or right-most) cell
+    for $from ... $to -> $pos {
+        $max = @shape[$pos] if @shape[$pos] > $max; # Raising wall, increase the maximum
+
+        # Remove water above the current maximum and fill it with air
+        @map[$pos; $_] = '.' for $max ..^ $height;
+    }
+}
-- 
cgit