Island Puzzle

题意翻译

给定一棵 $n$ 个点的树，每个点上都有一个 $[0,n-1]$ 的数，任意两点上的数都不同。 每次你可以交换 $0$ 所在的点和与其相连的任一点上的数，同时你可以最多加入一条边。 给定目标状态，你需要在加入的边数尽量小的前提下，求出最少的步数，或者判断无法达成目标。 $n \leq 2 \times 10^5$。

题目描述

A remote island chain contains $ n $ islands, with some bidirectional bridges between them. The current bridge network forms a tree. In other words, a total of $ n-1 $ bridges connect pairs of islands in a way that it's possible to reach any island from any other island using the bridge network. The center of each island contains an identical pedestal, and all but one of the islands has a fragile, uniquely colored statue currently held on the pedestal. The remaining island holds only an empty pedestal. The islanders want to rearrange the statues in a new order. To do this, they repeat the following process: first, they choose an island directly adjacent to the island containing an empty pedestal. Then, they painstakingly carry the statue on this island across the adjoining bridge and place it on the empty pedestal. It is often impossible to rearrange statues in the desired order using only the operation described above. The islanders would like to build one additional bridge in order to make this achievable in the fewest number of movements possible. Find the bridge to construct and the minimum number of statue movements necessary to arrange the statues in the desired position.

输入输出格式

输入格式

The first line contains a single integer $ n $ ( $ 2<=n<=200000 $ ) — the total number of islands. The second line contains $ n $ space-separated integers $ a_{i} $ ( $ 0<=a_{i}<=n-1 $ ) — the statue currently located on the $ i $ -th island. If $ a_{i}=0 $ , then the island has no statue. It is guaranteed that the $ a_{i} $ are distinct. The third line contains $ n $ space-separated integers $ b_{i} $ ( $ 0<=b_{i}<=n-1 $ ) — the desired statues of the $ i $ -th island. Once again, $ b_{i}=0 $ indicates the island desires no statue. It is guaranteed that the $ b_{i} $ are distinct. The next $ n-1 $ lines each contain two distinct space-separated integers $ u_{i} $ and $ v_{i} $ ( $ 1<=u_{i},v_{i}<=n $ ) — the endpoints of the $ i $ -th bridge. Bridges form a tree, and it is guaranteed that no bridge is listed twice in the input.

输出格式

Print a single line of integers: If the rearrangement can be done in the existing network, output $ 0\ t $ , where $ t $ is the number of moves necessary to perform the rearrangement. Otherwise, print $ u $ , $ v $ , and $ t $ ( $ 1<=u<v<=n $ ) — the two endpoints of the new bridge, and the minimum number of statue movements needed to perform the rearrangement. If the rearrangement cannot be done no matter how the new bridge is built, print a single line containing $ -1 $ .

输入输出样例

输入样例 #1

3
1 0 2
2 0 1
1 2
2 3

输出样例 #1

1 3 3

输入样例 #2

2
1 0
0 1
1 2

输出样例 #2

0 1

输入样例 #3

4
0 1 2 3
0 2 3 1
1 2
1 3
1 4

输出样例 #3

-1

说明

In the first sample, the islanders can build a bridge connecting islands $ 1 $ and $ 3 $ and then make the following sequence of moves: first move statue $ 1 $ from island $ 1 $ to island $ 2 $ , then move statue $ 2 $ from island $ 3 $ to island $ 1 $ , and finally move statue $ 1 $ from island $ 2 $ to island $ 3 $ for a total of $ 3 $ moves. In the second sample, the islanders can simply move statue $ 1 $ from island $ 1 $ to island $ 2 $ . No new bridges need to be built and only $ 1 $ move needs to be made. In the third sample, no added bridge and subsequent movements result in the desired position.

题意翻译

给定一棵 $n$ 个点的树，每个点上都有一个 $[0,n-1]$ 的数，任意两点上的数都不同。 每次你可以交换 $0$ 所在的点和与其相连的任一点上的数，同时你可以最多加入一条边。 给定目标状态，你需要在加入的边数尽量小的前提下，求出最少的步数，或者判断无法达成目标。 $n \leq 2 \times 10^5$。