Codeforces Round 109 (Div. 2)
C
Hometask
Codeforces
未评级
原题
← BD →
翻译中…

Sergey attends lessons of the $*N*$-ish language. Each lesson he receives a hometask. This time the task is to translate some sentence to the $*N*$-ish language. Sentences of the $*N*$-ish language can be represented as strings consisting of lowercase Latin letters without spaces or punctuation marks.

翻译中…

Sergey totally forgot about the task until half an hour before the next lesson and hastily scribbled something down. But then he recollected that in the last lesson he learned the grammar of $*N*$-ish. The spelling rules state that $*N*$-ish contains some "forbidden" pairs of letters: such letters can never occur in a sentence next to each other. Also, the order of the letters doesn't matter (for example, if the pair of letters "ab" is forbidden, then any occurrences of substrings "ab" and "ba" are also forbidden). Also, each pair has different letters and each letter occurs in no more than one forbidden pair.

翻译中…

Now Sergey wants to correct his sentence so that it doesn't contain any "forbidden" pairs of letters that stand next to each other. However, he is running out of time, so he decided to simply cross out some letters from the sentence. What smallest number of letters will he have to cross out? When a letter is crossed out, it is "removed" so that the letters to its left and right (if they existed), become neighboring. For example, if we cross out the first letter from the string "aba", we get the string "ba", and if we cross out the second letter, we get "aa".

翻译中…

Input

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The first line contains a non-empty string $*s*$, consisting of lowercase Latin letters — that's the initial sentence in $*N*$-ish, written by Sergey. The length of string $*s*$ doesn't exceed $10^{5}$.

翻译中…

The next line contains integer $*k*$ ($0 ≤ *k* ≤ 13$) — the number of forbidden pairs of letters.

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Next $*k*$ lines contain descriptions of forbidden pairs of letters. Each line contains exactly two different lowercase Latin letters without separators that represent the forbidden pairs. It is guaranteed that each letter is included in no more than one pair.

翻译中…

Output

翻译中…

Print the single number — the smallest number of letters that need to be removed to get a string without any forbidden pairs of neighboring letters. Please note that the answer always exists as it is always possible to remove all letters.

翻译中…

Note

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In the first sample you should remove two letters b.

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In the second sample you should remove the second or the third letter. The second restriction doesn't influence the solution.

翻译中…

样例

Input #1
ababa
1
ab
Output #1
2
InputCopy OutputCopy
Input #2
codeforces
2
do
cs
Output #2
1
InputCopy OutputCopy
题目信息
题号
155C
时间限制
2 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。