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A. QAQ time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output

"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!).

illustration by 貓屋 https://twitter.com/nekoyaliu

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 Copy QAQAQYSYIOIWIN output Copy 4 input Copy QAQQQZZYNOIWIN output Copy 3 Note

In the first example there are?4?subsequences "QAQ": "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN".

因為n的取值比較小，直接暴力

#include<bits/stdc++.h> using namespace std; typedef long long ll; const int inf = 0x3f3f3f3f; int main() { // freopen("shuju.txt","r",stdin);string a;cin>>a;int len=a.length();int ans=0;for(int i=0;i<len-2;i++){for(int j=i+1;j<len-1;j++){for(int k=j+1;k<len;k++){if(a[i]=='Q'&&a[j]=='A'&&a[k]=='Q')ans++;}}}cout<<ans<<endl;return 0; }

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