number of ways

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef tree<int,null_type,less<>,rb_tree_tag,tree_order_statistics_node_update> indexed_set;

#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define MOD 1000000007
#define PI 3.14159265
#define ceil(a, b) ((a / b) + (a % b ? 1 : 0))
#define imin INT_MIN
#define imax INT_MAX
#define nl '\n'

void Start_Crushing() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
}
//vector<int> dx = {0, 0, 1, -1, 1, 1, -1, -1}, dy = {1, -1, 0, 0, 1, -1, 1, -1};
//vector<int> dx = {0, 0, 1, -1}, dy = {1, -1, 0, 0};
int s, e, cnt = 0;

void cntWays(int curr){
    if(curr >= e){
        cnt += curr == e;
        return;
    }
    cntWays(curr + 1);
    cntWays(curr + 2);
    cntWays(curr + 3);
}

void solve(){
    cin >> s >> e;
    cntWays(s);
    cout << cnt;
}

int main(){
//    freopen("cakes.in", "r", stdin);
    Start_Crushing();

    int t = 1;
//        /*is Single Test case?*/ cin >> t;
    while (t--) {
        solve();
        if(!t) break;
        cout << "\n";
    }

    return 0;
}