Merge pull request #10578 from mattneleigh/pwc281

new file:   challenge-281/mattneleigh/perl/ch-1.pl

1 files changed, 54 insertions, 0 deletions

diff --git a/challenge-281/mattneleigh/perl/ch-1.pl b/challenge-281/mattneleigh/perl/ch-1.pl
new file mode 100755
index 0000000000..311236273b
--- /dev/null
+++ b/challenge-281/mattneleigh/perl/ch-1.pl
@@ -0,0 +1,54 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+use English;
+
+################################################################################
+# Begin main execution
+################################################################################
+
+my @chess_squares = (
+    "d3",
+    "g5",
+    "e6"
+);
+
+print("\n");
+foreach my $chess_square (@chess_squares){
+    printf(
+        "Input: \$coordinates = \"%s\"\nOutput: %s\n\n",
+        $chess_square,
+        is_chess_square_light($chess_square) ? "true" : "false"
+    );
+}
+
+exit(0);
+################################################################################
+# End main execution; subroutines follow
+################################################################################
+
+
+
+################################################################################
+# Determine whether a given square on a chessboard is light or dark, given its
+# coordinates in Algebraic Notation- file (a-h) and rank (1-8)
+# Takes one argument:
+# * The coordinates of the square in algebraic notation (e.g. "d3")
+# Returns:
+# * 0 if the square is dark; 1 if the square is light
+################################################################################
+sub is_chess_square_light{
+    my ($file, $rank) = split(//, shift());
+
+    return(
+        # Convert the file coordinate to a number
+        # (1-indexed) then determine whether each
+        # coordinate is even, and XOR the results
+        ((ord(lc($file)) - 96) % 2) ^ ($rank % 2)
+    );
+
+}
+
+
+