Eddy Wants Admission

Eddy goes to Taxila University, one of the renowned university in the world. He wants to get admission in this university but the head of the university won't allow him unless he proves his command on numbers. The head doesn't want to defame his university by admitting a fool so he takes an admission test. He gives Eddy two numbers $L$ and $R$. Now, Eddy is asked to tell the count of numbers be