Postional file schema creation without document instance (without flat file creation wizard) in biztalk

now i created flat file schema( for positional file) and my complexity is, For a scenario 10segments will be avaliable in the schema file all are optional elements so i fixed as min occur as 0, max occurs 36, 
For e.g: Generated instance to be like this 
<pre><Header>
<SEG1>
<SEG1_child1>111</SEG1_child1>
</SEG1>
<SEG2>
<SEG2_child1>222</SEG2_child1>
</SEG2>
<SEG3>
<SEG3_child1>333</SEG3_child1>
</SEG3><!-- upto SEG10-->
</Header>
</pre>

this can be generated while validating instance.(input: 111222333444555666777888999000),

now the input file like this (111222444555666888) means the output like this 
<pre>
<Header>
<SEG1>
<SEG1_child1>111</SEG1_child1>
</SEG1>
<SEG2>
<SEG2_child1>222</SEG2_child1>
</SEG2>
<SEG3>
<SEG3_child1>444</SEG3_child1>
</SEG3><!-- upto SEG10-->
</Header>
</pre>


My Question is: i want the output instance like this,
<pre>&lt;Header>
<SEG1>
<SEG1_child1>111</SEG1_child1>
</SEG1>
<SEG2>
<SEG2_child1>222</SEG2_child1>
</SEG2>
<SEG4>
<SEG4_child1>444</SEG4_child1>
</SEG4>
<SEG5>
<SEG5_child1>555</SEG5_child1>
</SEG5>
<SEG6>
<SEG6_child1>666</SEG6_child1>
</SEG6>
<SEG8>
<SEG8_child1>888</SEG8_child1>
</SEG8>
</Header>
</pre>


even i used  here as tag identifier concept means looking for so& so tag name,
offset concept also not working here,
:~