#include<bits/stdc++.h>
#define int long long

int l,r,T;

signed main(){
	std::cin>>T;
	while(T--){
		std::cin>>l>>r;
		int len=r-l+1;
		for(int i=len;;i--){
			int x=l%i,y=i-x+l;
			if(x==0) y=0;
//			fprintf(stderr,"i=%lld x=%lld and y=%lld\n",i,x,y);
			if(r-y>=i){
				printf("%lld\n",i);
				break;
			}
		} 
	}
}