#D2390. Random Forest Rank
Random Forest Rank
Random Forest Rank
Let's define rank of undirected graph as rank of its adjacency matrix in R^{n × n}.
Given a tree. Each edge of this tree will be deleted with probability 1/2, all these deletions are independent. Let E be the expected rank of resulting forest. Find E ⋅ 2^{n-1} modulo 998244353 (it is easy to show that E ⋅ 2^{n-1} is an integer).
Input
First line of input contains n (1 ≤ n ≤ 5 ⋅ 10^{5}) — number of vertices.
Next n-1 lines contains two integers u v (1 ≤ u, v ≤ n; u ≠ v) — indices of vertices connected by edge.
It is guaranteed that given graph is a tree.
Output
Print one integer — answer to the problem.
Examples
Input
3 1 2 2 3
Output
6
Input
4 1 2 1 3 1 4
Output
14
Input
4 1 2 2 3 3 4
Output
18
inputFormat
Input
First line of input contains n (1 ≤ n ≤ 5 ⋅ 10^{5}) — number of vertices.
Next n-1 lines contains two integers u v (1 ≤ u, v ≤ n; u ≠ v) — indices of vertices connected by edge.
It is guaranteed that given graph is a tree.
outputFormat
Output
Print one integer — answer to the problem.
Examples
Input
3 1 2 2 3
Output
6
Input
4 1 2 1 3 1 4
Output
14
Input
4 1 2 2 3 3 4
Output
18
样例
4
1 2
2 3
3 4
18
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