资源摘要:Recall the definition of a trie:A trie of size �n is a rooted tree with �n vertices and (�−1)(n−1) edges, where each edge is marked with a character;Each vertex in a trie represents a string. Let �(�)s(x) be the string vertex �x represents;The root of the trie represents an empty string. Let vertex �u be the parent of vertex �v, and let �c be the character marked on the edge connecting vertex �u and �v, we have �(�)s(v) = �(�)+�s(u)+c. Here ++ indicat