How to solve questions which has constraint ranging from 1 to 10^10000

Be more specific. I am assuming you mean how to handle such large numbers. Well, in case of Java I can say you should use BigInteger. If you are using python , it will automatically handle large numbers as such.

I am using c++ and the constraint range is of 10^10000 I got only partial marks for question the constraint was 1 to 10^10000

Make Google your friend, no one is going to help during contests.