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+#!/usr/bin/perl
+
+# Weekly Challenge 140 Task 1
+#
+# You are given two decimal-coded binary numbers, $a and $b.
+#
+# Write a script to simulate the addition of the given binary numbers.
+#
+# The script should simulate something like $a + $b. (operator overloading)
+
+use strict;
+
+my ($a, $b, $c, $final);
+my @test = qw (11 1 101 1 100 11);
+
+for ($c=0; $c<$#test+1; $c+=2) {
+  $a = $test[$c];
+  $b = $test[$c+1];
+
+  $final = binary_add($a, $b);
+  print "Input: \$a = $a; \$b = $b\n";
+  print "Output: $final\n\n";
+}
+
+sub binary_add {
+  my $x = shift;
+  my $y = shift;
+
+# Determine which number is larger
+  my $diff = length($x) - length($y);
+  my ($sum, $num, $i);
+  my (@arr1, @arr2, @num);
+  my $carry=0;
+
+# Append left with 0s to help with piecewise math.
+  if ($diff > 0) {
+    $diff = length($x);
+    $y = sprintf("%0${diff}d", $y);
+
+  }
+  elsif ($diff < 0) {
+    $diff = length($y);
+    $x = sprintf("%0${diff}d", $x);
+  }
+
+# Split numbers into pieces
+  @arr1=split(//,$x);
+  @arr2=split(//,$y);
+  for ($i=$#arr1; $i>-1;$i--) {
+    $sum=$arr1[$i]+$arr2[$i]+$carry;
+
+# If/elses to ensure no values greater than 1.
+    if ($sum eq 2) {
+      $sum = 0;
+      $carry = 1; 
+    }
+    elsif ($sum eq 3) {
+      $sum = 1;
+      $carry = 1;
+    }
+    else {
+      $carry = 0;
+    }
+    $num=$sum.$num
+  }
+
+# One last check for a carry.
+  $num="1".$num if $carry eq 1;
+  return "$num";
+}