Data commit

Task/Set-consolidation/Perl/set-consolidation.pl

@@ -0,0 +1,47 @@
+use strict;
+use English;
+use Smart::Comments;
+
+my @ex1 = consolidate( (['A', 'B'], ['C', 'D']) );
+### Example 1: @ex1
+my @ex2 = consolidate( (['A', 'B'], ['B', 'D']) );
+### Example 2: @ex2
+my @ex3 = consolidate( (['A', 'B'], ['C', 'D'], ['D', 'B']) );
+### Example 3: @ex3
+my @ex4 = consolidate( (['H', 'I', 'K'], ['A', 'B'], ['C', 'D'], ['D', 'B'], ['F', 'G', 'H']) );
+### Example 4: @ex4
+exit 0;
+
+sub consolidate {
+    scalar(@ARG) >= 2 or return @ARG;
+    my @result = ( shift(@ARG) );
+    my @recursion = consolidate(@ARG);
+    foreach my $r (@recursion) {
+        if (set_intersection($result[0], $r)) {
+            $result[0] = [ set_union($result[0], $r) ];
+        }
+        else {
+            push @result, $r;
+        }
+    }
+    return @result;
+}
+
+sub set_union {
+    my ($a, $b) = @ARG;
+    my %union;
+    foreach my $a_elt (@{$a}) { $union{$a_elt}++; }
+    foreach my $b_elt (@{$b}) { $union{$b_elt}++; }
+    return keys(%union);
+}
+
+sub set_intersection {
+    my ($a, $b) = @ARG;
+    my %a_hash;
+    foreach my $a_elt (@{$a}) { $a_hash{$a_elt}++; }
+    my @result;
+    foreach my $b_elt (@{$b}) {
+        push(@result, $b_elt) if exists($a_hash{$b_elt});
+    }
+    return @result;
+}