#include<bits/stdc++.h>
//using namespace std;
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define rep(i, j, n) for(int i = int(j); i < int(n); i++)
#define REP(i, j, n) for(int i = int(j); i <= int(n); i++)
#define per(i, j, n) for(int i = int(j); int(n) <= i; i--)
#define ALL(a) (a).begin(),(a).end()
#define revALL(a) (a).rbegin(),(a).rend()
#define pb push_back
#define mp std::make_pair
#define mtp std::make_tuple
#define ln "\n"
using std::endl;
using std::cin;
using std::cout;
#define ll long long
using std::vector;
using std::string;
using std::upper_bound;
using std::lower_bound;
const ll MOD = int(1e9+7);
const ll MAX = 1e6+10;
const ll inf = (1ll << 60);

//modpow
ll modpow(ll X, ll Y, ll mod){
    ll ret = 1;
    while(Y){
        if(Y & 1){
            ret *= X;
            ret %= mod;
        }
        X *= X;
        X %= mod;
        Y >>= 1;
    }
    return ret % mod;
}

//binary_indexed_tree
template<typename T>
struct binary_indexed_tree{
    int N;
    vector<T> bit;
    binary_indexed_tree(int n):N(n){
        bit.resize(N+1,0);
    }
    T addition(T a, T b){
        return a+b;
    }
    void add(int x,T a){
        x++;
        for(; x<=N; x+=(x&-x)) bit[x] = addition(bit[x], a);
    }
    T sum(int x){
        x++;
        T ret=0;
        for(; x>0; x-=(x&-x)) ret = addition(ret, bit[x]);
        return ret;
    }
    ll lower_bound(T X){
        if(sum(N-1)<X) return -1;
        ll ret=0, memo=1;
        T sum=0;
        while(memo*2 <= N) memo *= 2;
        while(0 < memo){
            if(memo+ret<=N && addition(sum, bit[memo+ret])<X){
                sum = addition(sum, bit[memo+ret]);
                ret+=memo;
            }
            memo/=2;
        }
        return ret;
    }
};

//main
int main(){
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    std::cout.tie(nullptr);
    cout << std::fixed << std::setprecision(15);
    ll T; cin >> T;
    while(T--){
        ll N,M; cin >> N >> M;
        // 1,2,3,...,M-1,0,1,2,3,...,M-1,0,1,2,3,...,
        ll ans = 0;
        if(M <= N){
            ans = M/2;
        }
        else{
            ans = (M-N)*(M-N+1)/2;
            ans += M/2;
        }
        cout << ans << ln;
    }
}