题目描述
Problem Description
In a certain country, a harvest festival is held annually at supermarkets, where crops from each town are gathered.
This country has $ N $ towns numbered $0, \ldots, N-1$. There are also $ M $ roads numbered $0, \ldots, M-1$, where road $ i $ connects town $ x_i $ and town $ y_i $ bidirectionally with a length of $ d_i $. Among all towns, supermarkets are located in $ K $ towns numbered $a_0, \ldots, a_{K-1}$.
The set of supermarkets hosting the harvest festival that year is determined by the following conditions:
- At least one town from all towns is selected to exhibit at the festival.
- To hold the festival while the crops are fresh, it is held at supermarkets within a shortest distance of $ D $ from all selected towns.
- As many supermarkets as possible are chosen to host the festival, so all eligible supermarkets host it.
For all subsets $A' \subseteq \{ a_0, \ldots, a_{K-1} \}$ of supermarkets, calculate the number of ways towns can be selected such that the harvest festival is held at $ A' $, modulo $ 998244353 $, and output the XOR of these counts.
Input Format
The input is given from the standard input in the following format:
$ N $ $ M $ $ K $ $ D $ $ a_0 $ $ a_1 $ $\ldots$ $ a_{K-1} $ $ x_0 $ $ y_0 $ $ d_0 $ $\vdots$ $ x_{M-1} $ $ y_{M-1} $ $ d_{M-1} $
Output Format
Output the answer.
Sample Input and Output
Sample Input #1
3 1 3 1
0 1 2
1 2 1
Sample Output #1
1
Sample Input #2
5 4 3 2
1 2 3
0 1 2
1 2 1
2 3 5
3 4 5
Sample Output #2
17
Sample Input #3
4 2 4 2
0 1 2 3
0 1 1
2 3 1
Sample Output #3
9
Sample Input #4
9 9 4 6
1 3 6 8
1 4 4
6 7 1
4 5 3
3 6 2
4 7 5
7 8 1
1 5 3
1 0 2
4 8 1
Sample Output #4
367
Notes/Hints
Constraints
- $1 \leq N \leq 10^5$
- $0 \leq M \leq \min \left(N(N-1)/2, 2 \times 10^5 \right)$
- $1 \leq K \leq \min(N, 20)$
- $1 \leq D \leq 10^9$
- $0 \leq a_i \leq N-1$
- $a_0, \ldots, a_{K-1}$ are distinct
- $0 \leq x_i, y_i \leq N-1$
- $1 \leq d_i \leq 10^9$
- All values in the input are integers
- When considering the undirected graph with towns as vertices and roads as edges, the graph does not contain multiple edges or self-loops
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分