#include<iostream>
using namespace std;
long long len, T,ans;
string s;
char str[100005];
bool flag;
int main(){
	cin>>T;
	while(T--){
		cin>>len;
		cin>>s; 
		int cnt=-1;
		for(int i=len-1;i>=0;i--){
			str[++cnt]=s[i];
		}
		for(int i=0;i<len;i++){
			if(s[i]=='A'&&str[i]=='T') ans+=i+1;
			else if(s[i]=='T'&&str[i]=='A') ans+=i+1;
			else if(s[i]=='C'&&str[i]=='G') ans+=i+1;
			else if(s[i]=='G'&&str[i]=='C') ans+=i+1;
			if(s[i]!='A'&&s[i]!='T'&&s[i]!='C'&&s[i]!='G'){
				ans=0;
			}
		}
		cout<<ans<<endl;
		ans=cnt=0;
	}
}