#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
void solve() {
    i64 L,R;
    cin >> L >> R;
    for ( i64 i = R-L ; i >= 1 ; i-- ) {
        i64 t = (L+i-1)/i;
        if ( L <= t*i && t*i <= R && L <= (t+1)*i && (t+1)*i <= R ) {
            cout << i << '\n';
            return;
        }
    }
}
int main() {
    int T = 1;
    cin >> T;
    while ( T-- ) {
        solve();
    }
}