Help Needed in Counting Primes SPOJ

Question link:

my solution : (WA)

I am getting WA . I am unable to figure out what is wrong in my solution.
I have used lazy propagation . while making the segment tree i m storing the value of 1 at leaves if the number is prime( to keep the count easy) or 0 if they are not prime. While updating the range i am adding 1 in [L,R] if the updated value is prime.

Can someone tell what’s wrong in my code.

Edit : I got the error. Ignore the post

I am not aware of Lazy Propagation, but why don’t you try BIT?
Implementation is easy too.

Thank You , i will definitely try this method .