#include <bits/stdc++.h>
#include <atcoder/all>

using namespace std;
using namespace atcoder;

struct Fast {
  Fast() {
    std::cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << setprecision(10);
  }
} fast;

#define all(a) (a).begin(), (a).end()
#define contains(a, x) ((a).find(x) != (a).end())
#define rep(i, a, b) for (int i = (a); i < (int)(b); i++)
#define rrep(i, a, b) for (int i = (int)(b)-1; i >= (a); i--)
#define writejoin(s, a) rep(_i, 0, (a).size()) cout << (a)[_i] << (_i + 1 < (int)(a).size() ? s : "\n");
#define YN(b) cout << ((b) ? "YES" : "NO") << "\n";
#define Yn(b) cout << ((b) ? "Yes" : "No") << "\n";
#define yn(b) cout << ((b) ? "yes" : "no") << "\n";

using ll = long long;
using mint = modint998244353;

mint fs(ll m, ll a, ll b) {
  a -= m;
  // sum[x=0~m]floor((x+a)/b);
  ll r = a % b;
  if (r < 0) r += b;
  mint ret = mint(m + 1) * ((a - r) / b);
  a = r;
  m += a + 1;
  // sum[x=0~m-1]floor(x/b);
  ll n = m / b;
  ret += mint(m % b) * n;
  ret += mint(b) * n * (n - 1) / 2;
  return ret;
}

int main() {
  int t;
  cin >> t;
  while (t--) {
    ll n, m, l, r;
    cin >> n >> m >> l >> r;
    mint ans = m + 1;
    ans += fs(m, r, n - 1);
    ans -= fs(m, l + n - 2, n - 1);
    cout << ans.val() << "\n";
  }
}