#include <bits/stdc++.h>

using ll=long long;
using namespace std;

#define rep_i(i, n) for (int i = 0; i < (n); ++i)
#define rep_ll(i, n) for (long long i = 0; i < (n); ++i)
#define r_rep_i(i, start, end) for (int i = (start); i < (end); ++i)
#define r_rep_ll(i, start, end) for (long long i = (start); i < (end); ++i)
#define debug_vi(v) copy((v).begin(), (v).end(), ostream_iterator<int>(cout, " "));
#define debug_vll(v) copy((v).begin(), (v).end(), ostream_iterator<long long>(cout, " "));
#define debug_vd(v) copy((v).begin(), (v).end(), ostream_iterator<double>(cout, " "));
#define sort_v(v) sort((v).begin(), (v).end()); //昇順
#define d_sort_vi(v) sort((v).begin(), (v).end(), greater<int>()); //降
#define d_sort_vll(v) sort((v).begin(), (v).end(), greater<long long>()); //降
#define d_sort_vd(v) sort((v).begin(), (v).end(), greater<double>()); //昇順
#define say(t) cout << (t) << endl;
#define sum_vi(v) accumulate((v).begin(), (v).end(), 0);
#define sum_vll(v)accumulate((v).begin(), (v).end(), 0LL);

ll gcd(ll a, ll b) { return b?gcd(b, a%b):a;}
ll lcm(ll a, ll b) { return a/gcd(a, b)*b;}

const int IINF=(1<<30);
const ll LLINF = 1LL<<60;

char BigAlphaToSmall(char a){
    if (a >= 65 && a <= 90){
        return a + 32;
    }
    return a;
}

char SmallAlphaToBig(char a){
    if (a >= 97 && a <= 122){
        return a - 32;
    }
    return a;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    int t;
    cin >> t;
    rep_i(i, t)
    {
        int l, r;
        cin >> l >> r;
        if (2*l > r)
        {
            cout << 0 << endl;
            continue;
        }
        ll hoge = r-(2*l)+2;
        ll hoge2 = r-(2*l)+1;
        ll ans = hoge*hoge2/2;
        cout << ans << endl;
    }
}
// acl1

#include<bits/stdc++.h>
using namespace std;
#define ll long long 

int main(){

    ll t;
    cin>>t;
    while(t--){
        ll l,r;
        cin>>l>>r;

        ll n=r-l-l+1;

        ll ans=((n)*(n+1))/2;
        if(n>0)
        cout<<ans<<endl;
        else{
            cout<<0<<endl;
        }


    }
}