题库练习 QAQ
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A11406 | QAQ

时间限制1s
内存限制256MB
通过 / 提交0/0

题目描述

"QAQ" is a word to denote an expression of crying. Imagine "Q" as eyes with tears and "A" as a mouth.

Now Diamond has given Bort a string consisting of only uppercase English letters of length $n$ . There is a great number of "QAQ" in the string (Diamond is so cute!).

![](/uploads/acgo/image/2377fc9b69e1e56b_34fb32159556.jpeg)illustration by 猫屋 https://twitter.com/nekoyaliuBort wants to know how many subsequences "QAQ" are in the string Diamond has given. Note that the letters "QAQ" don't have to be consecutive, but the order of letters should be exact.

输入格式

The only line contains a string of length $n$ ( $1<=n<=100$ ). It's guaranteed that the string only contains uppercase English letters.

输出格式

Print a single integer — the number of subsequences "QAQ" in the string.

输入输出样例

输入 #1
QAQAQYSYIOIWIN
输出 #1
4
输入 #2
QAQQQZZYNOIWIN
输出 #2
3
C++ 编辑器
输入
输出