For each case, the first line contains two addresses of nodes and a positive N (<= 10^5), where the two addresses are the addresses of the first nodes of the two words, and N is the total number of nodes. The address of a node is a 5-digit positive integer, and NULL is represented by -1. Then N lines follow, each describes a node in the format: Address Data Next where Address is the position of the node, Data is the letter contained by this node which is an English letter chosen from {a-z, A-Z}, and Next is the position of the next node.
For each case, simply output the 5-digit starting position of the common suffix. If the two words have no common suffix, output "-1" instead.
11111 22222 9 67890 i 00002 00010 a 12345 00003 g -1 12345 D 67890 00002 n 00003 22222 B 23456 11111 L 00001 23456 e 67890 00001 o 00010 00001 00002 4 00001 a 10001 10001 s -1 00002 a 10002 10002 t -1
67890 -1