#include <bits/stdc++.h>
using namespace std;
 
void mainSolve()
{
  int x,y;
  cin>>x>>y;

  if(x>y)
    cout<<"A";
  else 
    cout<<"B";

  cout<<endl;
  
}
 
int main()
{
  int t;
  cin>>t;

  while(t--)
  mainSolve();

  return 0;
}