Codeforces•Jun 27, 2025
QAQ
Hazrat Ali
Codeforces
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!).
Bort 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.
Input
The only line contains a string of length n (1 ≤ n ≤ 100). It's guaranteed that the string only contains uppercase English letters.
Output
Print a single integer — the number of subsequences "QAQ" in the string.
Examples
Input
QAQAQYSYIOIWIN
Output
4
Input
QAQQQZZYNOIWIN
Output
3
Solution
#include <bits/stdc++.h>
using namespace std;
int main()
{
string s;
cin >> s;
int ans = 0;
for (int i = 0; i < s.size(); i++)
{
for (int j = i + 1; j < s.size(); j++)
{
for (int k = j + 1; k < s.size(); k++)
{
if (s[i] == 'Q' and s[j] == 'A' and s[k] == 'Q')
{
ans++;
}
}
}
}
cout << ans << endl;
return 0;
}