Question

Input file format:

<Tariff>
<AA>10030</AA>
<AA>100</AA>
</Tariff>
<Tariff>
<AA>30004</AA>
<AA>30001</AA>
</Tariff>
<Tariff>
<AA>Account division</AA>
<AA>AIR</AA>
<AA>AA</AA>
<AA>10039</AA>
</Tariff>

Output format :
Output should be aligned in a manner of Open Tag of “<Tariff>” & Having End Tag of “<\Tariff>” also separated by comma separator.

Output :

<Tariff>,<AA>10030</AA>,<AA>100</AA>,</Tariff>
<Tariff>,<AA>30004</AA>,<AA>30001</AA>,</Tariff>
<Tariff>,<AA>Account division</AA>,<AA>AIR</AA>,<AA>AA</AA>,<AA>10039</AA>,</Tariff>

Answer 1

vim -U file.txt -c 'g/^<Tariff>$/ .,/^<\/Tarrif>$/ - 1 s/$/,/' -c 'g/^<Tariff>,$/ .,/^<\/Tarrif>$/ join!' -c 'wq'

Will only work if your Tariff tags are alone on their own lines without heading nor trailing spaces.

Hope you will start accepting answers.