Problem7343--ABC235 —— Ex - Painting Weighted Graph

7343: ABC235 —— Ex - Painting Weighted Graph

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

Given is an undirected graph with N vertices and M edges. The i-th edge connects Vertices $A_i$ and $B_i$ and has a weight of $C_i$.
Initially, all vertices are painted black. You can do the following operation at most K times.
  • Operation: choose any vertex v and any integer x. Paint red all vertices reachable from the vertex vv by traversing edges whose weights are at most x, including v itself.
How many sets can be the set of vertices painted red after the operations?
Find the count modulo 998244353.

Input

Input is given from Standard Input in the following format:
$N\ M\ K$
$A_1\ B_1\ C_1$
$\vdots$
$A_M\ B_M\ C_M$

Output

Print the answer.

Constraints

$2≤N≤10^5$
$0 \leq M \leq 10^5$
$1 \leq K \leq 500$
$1 \leq A_i,B_i \leq N$
$1 \leq C_i \leq 10^9$
All values in input are integers.

Sample 1 Input

3 2 1
1 2 1
2 3 2

Sample 1 Output

6

For example, an operation with (v,x)=(2,1) paints Vertices 1,2 red, and an operation with (v,x)=(1,0) paints Vertex 1.

After at most one operation, the set of vertices painted red can be one of the following six: {},{1},{2},{3},{1,2},{1,2,3}.

Sample 2 Input

5 0 2

Sample 2 Output

16
The given graph may not be connected.

Sample 3 Input

6 8 2
1 2 1
2 3 2
3 4 3
4 5 1
5 6 2
6 1 3
1 2 10
1 1 100

Sample 3 Output

40
The given graph may have multi-edges and self-loops.

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