B'Given a tree consisting of n vertices. A tree is a connected undirected graph without cycles. Each edge of the tree has its weight, w_i . Your task is to count the number of different graphs that satisfy all four conditions: Two graphs are considered different if their sets of edges are different, taking into account the weights of the edges. The answer can be large, output it modulo 998244353 . The first line contains an integer t ( 1 <= t <= 10^4 ) -- the number of test cases. The first line of each test case contains two integers n and S ( 2 <= n <= 2 cdot 10^5, 1 <= S <= 10^9 ) -- the number of vertices and the upper bound of the weights. Then follow n-1 lines describing the tree, the i -th line contains three integers u_i , v_i , and w_i ( 1 <= u_i,v_i <= n, u_i ne v_i, 1 <= w_i <= S ) -- an edge in the tree with weight w_i . It is guaranteed that the sum of n for all tests does not exceed 2 cdot 10^5 . For each test, output the number of different graphs that satisfy the conditions, modulo 998244353 . In the first sample, there is only one graph, which is the given tree. In the second samle, the given tree looks like this: '...