Hi Ragul,
One solution coming in mind is create a proprty in your project config file ex- Response_value and give some value and expand it in your response
<A>{{Response_Value}}+1</A>
<B>{{Response_Value}}+2</B>
Now you need to apply the filter in your response and capture value of B and save that in Response_Value property.
Hope this will solve your issue.
Thanks,
Vinay Nagariya