Kindly help me to write a perl programme in this regard.

1. Construct a detailed specification of the problem.
2. Design an algorithm to fit the specification.
3. Write Perl code to implement the algorithm.
4. Write a test suite against the specification to prove that it has been met. (Once you become more proficient at this it is advisable to write the tests before the implementation.)
5. Document everything.

Use strict and warnings always. Read perlintro for the basics and then the other relevant parts of the documentation. Post back here with details if/when you get stuck.

Happy landings!