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+#!perl
+use strict;
+use warnings FATAL => qw(all);
+
+=prompt
+You are given an array of integers.
+
+Write a script to return the sum of total XOR for every subset of given array.
+
+Example 1
+
+Input: @ints = (1, 3)
+Output: 6
+
+Subset [1],    total XOR = 1
+Subset [3],    total XOR = 3
+Subset [1, 3], total XOR => 1 XOR 3 => 2
+
+Sum of total XOR => 1 + 3 + 2 => 6
+
+
+Example 2
+
+Input: @ints = (5, 1, 6)
+Output: 28
+
+Subset [5],       total XOR = 5
+Subset [1],       total XOR = 1
+Subset [6],       total XOR = 6
+Subset [5, 1],    total XOR => 5 XOR 1 => 4
+Subset [5, 6],    total XOR => 5 XOR 6 => 3
+Subset [1, 6],    total XOR => 1 XOR 6 => 7
+Subset [5, 1, 6], total XOR => 5 XOR 1 XOR 6 => 2
+
+Sum of total XOR => 5 + 1 + 6 + 4 + 3 + 7 + 2 => 28
+
+
+Example 3
+
+Input: @ints = (3, 4, 5, 6, 7, 8)
+Output: 480
+
+=cut
+
+use Test2::V0 -no_srand => 1;
+
+is(total_xor(1, 3), 6, 'Example 1');
+is(total_xor(5, 1, 6), 28, 'Example 2');
+is(total_xor(3, 4, 5, 6, 7, 8), 480, 'Example 3');
+done_testing();
+
+sub total_xor
+{
+     my $iter = subsets(\@_);
+     my $xor_sum = 0;
+     while (my $p = $iter->()) 
+     {
+          next unless @$p;
+          $xor_sum += eval join('^', @$p);
+     }
+     return $xor_sum;
+}
+
+sub subsets
+{
+    my $aref = $_[0];
+    my $length = scalar @$aref;
+    my $total = 2 ** $length; # Total number of subsets
+    
+    my $current = 0; # Start from the first bitmask
+    
+    return sub 
+    {
+          if ($current >= $total) 
+          {
+               return undef; # All subsets are generated
+          }
+        
+          # Generate the current subset based on the bitmask
+          my $bitmask = sprintf("%0${length}b", $current);
+          my @bits = reverse split(//, $bitmask);
+          my @included = grep { $bits[$_] == 1 } 0 .. $#bits;
+        
+          $current++; # Increment the bitmask
+        
+          return [@{$aref}[@included]]; # Return the subset
+    };
+}