Merge pull request #3556 from pkmnx/branch-for-100

challenge #100, no. 2

1 files changed, 44 insertions, 0 deletions

diff --git a/challenge-100/pkmnx/raku/ch-2.raku b/challenge-100/pkmnx/raku/ch-2.raku
new file mode 100755
index 0000000000..efc91d62f7
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+++ b/challenge-100/pkmnx/raku/ch-2.raku
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+#!/usr/bin/env raku
+
+# see usage: 
+#
+#  pk@pkx:~/stuff/raku/perlweeklychallenge-club/challenge-100/pkmnx/raku$ cat input.1 
+#  1
+#  2,4
+#  6,4,9
+#  5,1,7,2
+#  pk@pkx:~/stuff/raku/perlweeklychallenge-club/challenge-100/pkmnx/raku$ ./ch-2.raku < input.1
+#  The minimum path sum from top to bottom: 1 + 2 + 4 + 1 = 8
+#  
+#  [1]
+#  [2] 4
+#  6 [4] 9
+#  5 [1] 7 2
+#
+
+our $cch = [];
+sub MAIN() { 
+   my ( $mvls, $out, $lsz )  = ( [], [], 0 );
+   ## take input
+   my $d = lines().map(*.comb(/\d+/));
+   ## validate
+   for $d { my $nsz = $_.elems; die("bad input!") if $lsz > 0 && $nsz != $lsz + 1; $lsz = $nsz };
+   ## run
+   f($d,0,0);
+   ## display - distinguish lowest val per line in "[]" and display sum
+   for (^$d) -> $y {
+      my $m = $cch[$y].pairs.min(*.value);
+      $out.push( (^$d[$y]).map({ my $v = $d[$y][$_]; $_ == $m.key ??($mvls.push($v) && "[$v]") !!$v }).join(" ") );
+   }
+   say "The minimum path sum from top to bottom: " ~ $mvls.join(" + ") ~ " = " ~ $mvls.sum ~ "\n";
+   say $out.join("\n");
+}
+
+sub f ($d, $y, $x)  {
+   ! $d[$y][$x].defined && return Nil;
+   $cch[$y][$x].defined && return $cch[$y][$x];
+   ## recur
+   my $ar = (0,1).map({f($d, $y +1, $x +$_)}).grep(*.defined);
+   ## set cache elem to min of path from bottom up
+   return $cch[$y][$x] = $d[$y][$x] + ( $ar.elems >0 ??$ar.min !!0 );
+}