Hi monks, i have a file which contains the below mentioned input, if the file has to follow <main> tag follow <sub1> follow <sub2> and <sub3>. If the order changes, the error message has to display. Assume the file may contain more than 1000 lines like this. Please help me. 

<main>Ability-oriented motivation, 00206.p0105
<main>Ability test
<sub1>in conjunction with achievement batteries, 00226.p0085
<sub3>definition, 00226.g0005
<main>Aboriginal athletes, 00954.p0155
<sub2>Absolutism, 00688.p0010

[download]

Thanks in advance,
Regards,
Gubendran

Retitled by davido from 'Problem in my file'.

In reply to How to validate file format by gube

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