CF464C.Substitutes in Number
普及/提高-
通过率:0%
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题目描述
Andrew and Eugene are playing a game. Initially, Andrew has string s , consisting of digits. Eugene sends Andrew multiple queries of type " di→ti ", that means "replace all digits di in string s with substrings equal to ti ". For example, if s=123123 , then query " 2→00 " transforms s to 10031003 , and query " 3→ " ("replace 3 by an empty string") transforms it to s=1212 . After all the queries Eugene asks Andrew to find the remainder after division of number with decimal representation equal to s by 1000000007 (109+7) . When you represent s as a decimal number, please ignore the leading zeroes; also if s is an empty string, then it's assumed that the number equals to zero.
Andrew got tired of processing Eugene's requests manually and he asked you to write a program for that. Help him!
输入格式
The first line contains string s ( 1<=∣s∣<=105 ), consisting of digits — the string before processing all the requests.
The second line contains a single integer n ( 0<=n<=105 ) — the number of queries.
The next n lines contain the descriptions of the queries. The i -th query is described by string " di -> ti ", where di is exactly one digit (from 0 to 9), ti is a string consisting of digits ( ti can be an empty string). The sum of lengths of ti for all queries doesn't exceed 105 . The queries are written in the order in which they need to be performed.
输出格式
Print a single integer — remainder of division of the resulting number by 1000000007 (109+7) .
输入输出样例
输入#1
123123 1 2->00
输出#1
10031003
输入#2
123123 1 3->
输出#2
1212
输入#3
222 2 2->0 0->7
输出#3
777
输入#4
1000000008 0
输出#4
1
说明/提示
Note that the leading zeroes are not removed from string s after the replacement (you can see it in the third sample).