Codeforces Round#447 Div2 QAQ
"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 lengthn. 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.
The only line contains a string of length n (1 ≤ n ≤ 100). It's guaranteed that the string only contains uppercase English letters.
Print a single integer — the number of subsequences "QAQ" in the string.
QAQAQYSYIOIWIN
4
QAQQQZZYNOIWIN
3
In the first example there are 4 subsequences "QAQ": "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN".
题意: 给一个字符串，让你找出含有多少个QAQ
题解:水题，三层循环直接暴力解出来
#include <bits/stdc++.h>
using namespace std;
int main()
{
string s;
cin>>s;
int l=s.length();
int ans=0;
for(int i=0;i<l;i++)
{
for(int j=i+1;j<l;j++)
{
for(int k=j+1;k<l;k++)
{
if(s[i]=='Q'&&s[j]=='A'&&s[k]=='Q')
{
ans++;
}
}
}
}
cout<<ans<<endl;
return 0;
}