Guess Who Delivers

Anany and Manik need to deliver pizzas across the city, which can be considered as a tree consisting of $N$ nodes and $N-1$ edges. The drivers can start at any of the nodes at the beginning of the first day. They need not start at the same nodes. - There are $M$ days on which deliveries are to made. On the $i$-th day, the pizzas must be picked up from node $S_i$ and delivered to node $D_i$. Exa