iiitv/ChefLib

//Code Copyright: Sanskar Jain, Software Engineering 2nd Year, DTU

#include <iostream>
#include <algorithm>
#include <map>
#include <cstring>
using namespace std;

int main() {
    int t;
    cin>>t;
    while(t--){
        map<char,int> c,d;
        map<char,int>::iterator it;
        string a,b;
        int e[26],f[26],g[501],h[501];
        memset(e,0,sizeof(e));
        memset(f,0,sizeof(f));
        memset(g,0,sizeof(g));
        memset(h,0,sizeof(h));
        cin>>a>>b;
        if(a==b){
            cout<<"B\n";
            continue;
        }
        sort(a.begin(),a.end());
        sort(b.begin(),b.end());
        if(a==b){
            cout<<"B\n";
            continue;
        }
        for(int i=0;i<a.length();i++){
            e[a[i]-97]++;
            if(c.find(a[i])!=c.end()){
                c[a[i]]++;
            }
            else{
                c.insert(pair<char,int>(a[i],1));
            }
        }
        for(int i=0;i<b.length();i++){
            f[b[i]-97]++;
            if(d.find(b[i])!=d.end()){
                d[b[i]]++;
            }
            else{
                d.insert(pair<char,int>(b[i],1));
            }
        }
        for(int i=0;i<26;i++){
            g[e[i]]++;
            h[f[i]]++;
        }
        char winner='B';
        int flag=0;
        for (it=c.begin(); it!=c.end(); ++it){
            if(it->second>=2&&d.find(it->first)==d.end()){
                winner='A';
                goto result;
            }
        }
        for (it=c.begin(); it!=c.end(); ++it){
            if(d.find(it->first)==d.end()){
                flag=1;
            }
        }
        if(flag==0){
            winner='B';
            goto result;
        }
        for(int i=0;i<26;i++){
            if(f[i]==1&&e[i]==0){
                winner='B';
                goto result;
            }
        }
        flag=0;
        if(g[1]!=0){
            for (it=d.begin(); it!=d.end(); ++it){
                if(c.find(it->first)==c.end()){
                    flag=1;
                }
            }
            if(flag==0){
                winner='A';
                goto result;
            }
        }
        result:
        cout<<winner<<"\n";}
    return 0;
}