Gym Freaks

There are two friends Amit and Saurav, Amit is a gym freak he goes to the gym with a regular schedule of $P$ slots during the gym timings, where each $i^{th}$ slot is defined between $a_{i}$ and $b_{i}$. Seeing his friend Amit, Saurav also wants to go to the gym, he asks the gym manager for the slots, he gives $Q$ slots for the gym timings, where each $i^{th}$ slot is defined between $c_{i}$ and $