X: a b c j k g e h i
Y: a b d e f h i
Z: a z c d f g h i

##</code><code>##

X: a b [c j k g e] h i
Y: a b [d e f]     h i
x: a [b] c [j k] g [e] h i
Z: a [z] c [d f] g [ ] h i

##</code><code>##

X: a | b [c j k g e] h i
Y: a | b [d e f]     h i
x:   | [b] c [j k] g [e] h i
Z: a | [z] c [d f] g [ ] h i

##</code><code>##

X: a b   | [c j k g e] h i
Y: a b   | [d e f]     h i
x:       | c [j k] g [e] h i
Z: a [z] | c [d f] g [ ] h i

##</code><code>##

X: a b         | c | [j k g e] h i
Y: a b [d e f] |   |     h i
x:             |   | [j k] g [e] h i
Z: a   [z]     | c | [d f] g [ ] h i

##</code><code>##

X: a b   c     | [j k g e] h i
Y: a b [d e f] |     h i
x:             | [j k] g [e] h i
Z: a   z c     | [d f] g [ ] h i

##</code><code>##

X: a b   c j k        | g [e] h i
Y: a b        [d e f] | h i
x:                    | [e] h i
Z: a   z c    [d f]   | g [ ] h i

##</code><code>##

X: a b   c j k        | g | [e] h i
Y: a b        [d e f] |   | h i
x:                    |   | [e] h i
Z: a   z c    [d f]   | g | [ ] h i

##</code><code>##

X: a b   c j k           g | [e] h i
Y: a b         d [[e] f]   | h i
x:                         | [e] h i
Z: a   z c     d [    f] g | [ ] h i

##</code><code>##

X: a b   c j k       g | [e] h i
Y: a b         d e f   | h i
x:                     | [e] h i
Z: a   z c     d   f g | [ ] h i

##</code><code>##

X: a b   c j k       g e | h i
Y: a b         d e f     | h i
x:                       | h i
Z: a   z c     d   f g   | h i

##</code><code>##

X: a b   c j k       g e h i
Y: a b         d e f     h i
x:                       h i
Z: a   z c     d   f g   h i

##</code><code>##

my @seq= GetSequences(); # ( \@seq0, \@seq1, \@seq2, ... );
my @out= DiffMerge( 1, @seq );

sub DiffMerge
{
    my( $finish, @seq )= @_;
    my @diff= map {
        DiffToMerge->new( $_, $seq[-1] )
    }   @seq[ 0 .. $#seq-1 ];
    my @out;
    for my $i (  0 .. $#{ $seq[-1] }  ) {
        my @row;
        my $same= 0;
        my %sublists;
        my @flush;
        for my $d (  0 .. $#diff  ) {
            for(  $diff[$d]->SubList()  ) {
                $sublists{$d}= $_   if  $_;
            }
            if(  $diff[$d]->Same($i)  ) {
                $same++;
                push @flush, $d   if  $sublists{$d};
                push @row, $diff[$d]->Shift();
            } else {
                push @row, undef;
            }
        }
        if(  @flush  ) {
            for my $row (  DiffMerge( 0, values %sublists )  ) {
                my @subrow;
                for my $d (  keys %sublist  ) {
                    $subrow[$d]= $diff[$d]->SublistOffset() + shift @$row;
                }
                push @out, \@subrow;
            }
            FlushSublist( \@out, $_, $diff[$_] )
                for  @flush;
        }
        if(  $same  ) {
            push @row, $i;
            push @out, \@row;
        } else {
            my @r;
            $r[@diff]= $i;
            push @out, \@r;
        }
    }
    if(  $finish  ) {
        FlushSublist( \@out, $_, $diff[$_] )
            for  0 .. $#diff;
    }
    return @out;
}