I am getting only 50 marks

Hellp Me what is wrong in the code or give some test case so that i can figure out error
my code link: https://ide.codingblocks.com/s/165130

Input

4
1 15
4 1
7 1
10 1

Your Output

3

Expected Output

1

I hope I’ve cleared your doubt. I ask you to please rate your experience here
Your feedback is very important. It helps us improve our platform and hence provide you
the learning experience you deserve.

On the off chance, you still have some questions or not find the answers satisfactory, you may reopen
the doubt.