abbb.cpp

/**
  *
  * @Author     : Vinay Kushwaha (iamvinayvk)
  *
  * @DateTime   : 10/18/2020 12:24:08 PM
  *
  */

#include<bits/stdc++.h>
using namespace std;

#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define ll long long int
#define w(t) int t;cin>>t;while(t--)
#define mod 1000000007
#define all(x) x.begin(),x.end()
#define F first
#define S second
#define vi vector<int> 
#define vll vector<long long>
#define FOR(start,end,increment) for(ll i=start;i<end;i+=increment)

ll gcd(ll a, ll b)
{
	if(a==0)
		return b;
	return gcd(b%a,a);
}



int main(){
	
		fast
		w(t)
		{
			string s;
			cin>>s;
			stack<char> st;
			st.push(s[0]);
			for(int i=1;i<s.length();i++)
			{
				if(s[i]=='B'&&!st.empty())
				{
					st.pop();
					continue;
				}
				st.push(s[i]);

			}
			cout<<st.size()<<"\n";
		}


	return 0;
}