Hi CF Community:

Today I was solving the problem Farmcraft (http://main.edu.pl/en/archive/oi/21/far). Basically in this problem, you start at the root of a tree, and when you reach a node, you start a timer in that node(except for the root, which only starts when you visit it last). Each node has a time value t_i, and a timer in that node ends when it reaches t_i. What is the minimum amount of time for all timers to end, if you walk the tree in the optimal way.

My idea was to binary search the minimum time, and then subtract this from each node's t_i. Then, this gives the maximum time that you can reach each node. But how should I check if its possible to satisfy all maximum times. Or is there another solution?