// Problem: Empty the String
// Contest: CodeChef - START162B
// URL: https://www.codechef.com/START162B/problems/EMPTYSTR
// Memory Limit: 256 MB
// Time Limit: 1000 ms
// 2024-11-27 21:13:00
// Submission by : _o7_

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll_max 1e18
#define MOD 1000000007
#define yes cout<<"YES"<<endl
#define no cout<<"NO"<<endl
#define o7 {ios_base::sync_with_stdio(0); cin.tie(0);}
#define pb push_back
#define mp make_pair
#define it(x) (x).begin(), (x).end()
#define rit(x) (x).rbegin(), (x).rend()
using namespace __gnu_pbds;
using namespace std;

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

int binpow(int a,int b)
{
    if(b==0)
    {
        return 1;
    }
    if(b%2)
    {
        return (a*binpow(a,b-1))%MOD;
    }
    return binpow((a*a)%MOD,b/2);
}

int32_t main(){
	o7
    int t;
    cin>>t;
    while(t--){
        int n;
        cin>>n;
        string s;
        cin>>s;
        set<int>a,b;
        for(int i=0;i<n;i++)
        {
        	if(s[i]=='A')a.insert(i);
        	else b.insert(i);
        }
        int ans=0;
        while(true)
        {
        	if(a.empty())
        	{
        		break;
        	}
        	if(b.empty())
        	{
        		break;
        	}
        	auto as=*a.begin();
        	auto bs=*b.begin();
        	int flag=0;
        	if(as<bs)
        	{
        		int temp=as;
        		a.erase(as);
        		ans++;
        		auto it=lower_bound(it(b),as);
        		while(true)
        		{
        			if(it==b.end() ||  it==a.end())break;
        			temp=*it;
        			if(flag==0)
        			{
        				b.erase(temp);
        				flag=1;
        				it=lower_bound(it(a),temp);
        			}
        			else
        			{
        				a.erase(temp);
        				flag=0;
        				it=lower_bound(it(b),temp);
        			}
        		}
        	}
        	else
        	{
        		flag=1;
        		int temp=bs;
        		b.erase(bs);
        		ans++;
        		auto it=lower_bound(it(a),bs);
		        	// cout<<temp<<endl;
        		while(true)
        		{
        			if(it==b.end() ||  it==a.end())break;
        			temp=*it;
        			if(flag==0)
        			{
        				b.erase(temp);
        				flag=1;
        				it=lower_bound(it(a),temp);
        			}
        			else
        			{
        				a.erase(temp);
        				flag=0;
        				it=lower_bound(it(b),temp);
        			}
        		}	
        	}
        }
        	ans+=(a.size()+b.size());
        	cout<<ans<<endl;
    }
    
    return 0;
}