#include<bits/stdc++.h>
#define int long long
using namespace std;
using ll = long long;
using ld = double;
const ll mod = 1e9 + 7;
const ll inf = 1e15 + 5;
const int N = 5e6 + 5;

void solve(){
    int l,r;
    cin>>l>>r;
    int num=r-l+1;
    while(num){
        int n1=r/num;
        int n2=n1*num;
        if(n2>l){
            if(n2-num>=l){
                cout<<num<<'\n';
                return;
            }
        }
        num--;
    }
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
//    cout<<fixed<<setprecision(6);
//    srand(time(0));
    int T = 1;
    cin >> T;
    while (T--)solve();
    return 0;
}