From 20e0eea9e5da183cc865aef22e65b84db07d5d59 Mon Sep 17 00:00:00 2001
From: Ruben Westerberg <drclaw@mac.com>
Date: Fri, 12 Jul 2019 23:21:55 +1000
Subject: Added ch-2 p5 solution

---
 challenge-016/ruben-westerberg/perl5/ch-2.pl | 38 ++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100755 challenge-016/ruben-westerberg/perl5/ch-2.pl

diff --git a/challenge-016/ruben-westerberg/perl5/ch-2.pl b/challenge-016/ruben-westerberg/perl5/ch-2.pl
new file mode 100755
index 0000000000..b9b9e40927
--- /dev/null
+++ b/challenge-016/ruben-westerberg/perl5/ch-2.pl
@@ -0,0 +1,38 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use bigint;;
+use Digest::SHA qw(sha256 sha256_hex);
+use v5.26;
+
+my @addresses=@ARGV;
+@addresses= qw<1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2
+	3J98t1WpEZ73CNmQviecrnyiWrnqRhWNLy> unless @addresses;
+
+my %b;
+for ("1".."9","A".."H","J".."N","P".."Z","a".."k","m".."z") {
+	state $i=0;
+	$b{$_}=$i++;
+}
+
+for (@addresses) {
+	print "Testing Address: $_\n";
+	if (/[IlO]/) { print  "Invalid characters found: $_\n"; next};
+	my $sum=0;
+	my @a=reverse (split ("", $_));
+	while (my ($k,$v)=each @a) {
+		my $in=$b{$v};
+		$sum+=$in *(58**$k);;
+	}
+	my $bytes=$sum->as_bytes();
+	unless (length $bytes <= 25) { print  "Invalid length: $_\n";next }
+	my $buff='';
+	vec($buff,$_,8)=0x00 for (0..24);
+	my $offset=length($buff)-length($bytes);
+	substr($buff,$offset,length($bytes),$bytes);
+	my $check= substr(sha256(sha256(substr $buff,0,21)),0,4);
+	my $inCheck=substr($buff,21,4);
+	unless ($check eq $inCheck) { print "Check sum mismatch: $_\n";next};
+	print "Address OK: $_\n\n";
+
+}
-- 
cgit