Hi monks,
I have a string like this,
$str1='
<x><chapter>
<chapnum>1</chapnum>
</chapter>
<x><chapter>
<chapnum>1A</chapnum>
</chapter>
<chapter>
<chapnum>1B</chapnum>
</chapter>
<x><chapter>
<chapnum>1</chapnum>
</chapter>
<chapter>
<chapnum>3</chapnum>
</chapter>
<x><chapter>
<chapnum>1A</chapnum>
</chapter><x>';

[download]

I need to delete <x> tag having the condition is
First <x> tag after <chapnum>1</chapnum> with <chapnum>1A</chapnum> tags
that is 
<x><chapter><chapnum>1</chapnum></chapter><x><chapter><chapnum>1A</cha
+pnum>

[download]
</code>
to be 
<x><chapter><chapnum>1</chapnum></chapter><chapter><chapnum>1A</chapnu
+m>

[download]
</code>
i don't want to remove the last
<x><chapter><chapnum>1A</chapnum>
my output should look like this 
<x><chapter>
<chapnum>1</chapnum>
</chapter>
<chapter>
<chapnum>1A</chapnum>
</chapter>
<chapter>
<chapnum>1B</chapnum>
</chapter>
<x><chapter>
<chapnum>1</chapnum>
</chapter>
<chapter>
<chapnum>3</chapnum>
</chapter>
<x><chapter>
<chapnum>1A</chapnum>
</chapter><x>

[download]

I have tried like this,
$s1='<x><chapter>\s*<chapnum>1</chapnum>';
$s2='<chapter>\s*<chapnum>1A</chapnum>';

$str1 =~s#($s1)(.*?)<x>?=($s2)#$1$2$3#gsi;

[download]
Thanks in advance

In reply to Pattern matching problem by Anonymous Monk

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