B'We define a spanning tree of a graph to be a BFS tree rooted at vertex s if and only if for every node t the shortest distance between s and t in the graph is equal to the shortest distance between s and t in the spanning tree. Given a graph, we define f(x,y) to be the number of spanning trees of that graph that are BFS trees rooted at vertices x and y at the same time. You are given an undirected connected graph with n vertices and m edges. Calculate f(i,j) for all i , j by modulo 998 ,244 ,353 . The first line contains two integers n , m ( 1 <= n <= 400 , 0 <= m <= 600 ) -- the number of vertices and the number of edges in the graph. The i -th of the next m lines contains two integers a_i , b_i ( 1 <= q a_i, b_i <= q n , a_i < b_i ), representing an edge connecting a_i and b_i . It is guaranteed that all edges are distinct and the graph is connected. Print n lines, each consisting of n integers. The integer printed in the row i and the column j should be f(i,j) bmod 998 ,244 ,353 . The following picture describes the first example. The tree with red edges is a BFS tree rooted at both 1 and 2 . Similarly, the BFS tree for other adjacent pairs of vertices can be generated in this way. '...