#include<bits/stdc++.h>
using namespace std;
#define rep(i,n,k); for(ll i = k; i < (int)(n); i++)
#define rep1(i, n) for(ll i = 0; i < (n); ++i)
using ll = long long;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

int main() {
 ll t;
 cin>>t;
 rep(i,t,0){
 	ll n,m;
 	cin>>n>>m;
 	ll n1=n/4,m1=m/4,m2=m%4,n2=n%4;
 	if(n>m){
 	 if(n2!=0){
 	 	cout<<n1+1<<endl;
 	 }else{
 	 	cout<<n1<<endl;
 	 }
 	}else{
 		n-=4*n1;
 		m-=4*m1;
 		ll ans1=(m-n)/8,ans2=(m-n)%8;
 		if(ans2!=0){
 			cout<<ans1+1<<endl;
 		}else{
 			cout<<ans1<<endl;
 		}
 		
 	}
 }
}