#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
int main(){
  int T;
  cin >> T;
  for (int i = 0; i < T; i++){
    long long N, M, L, R;
    cin >> N >> M >> L >> R;
    M++;
    R++;
    vector<long long> x = {0, N - 1, M % (N - 1), L % (N - 1), R % (N - 1)};
    sort(x.begin(), x.end());
    x.erase(unique(x.begin(), x.end()), x.end());
    int cnt = x.size() - 1;
    vector<long long> A(cnt + 1, 0);
    A[0] += M / (N - 1) + 1;
    A[lower_bound(x.begin(), x.end(), M % (N - 1)) - x.begin()]--;
    vector<long long> B(cnt + 1, 0);
    B[0] += R / (N - 1) + 1;
    B[lower_bound(x.begin(), x.end(), R % (N - 1)) - x.begin()]--;
    B[0] -= L / (N - 1) + 1;
    B[lower_bound(x.begin(), x.end(), L % (N - 1)) - x.begin()]++;
    for (int j = 0; j < cnt; j++){
      A[j + 1] += A[j];
      B[j + 1] += B[j];
    }
    long long ans = 0;
    for (int j = 0; j < cnt; j++){
      ans += (A[j] % MOD) * (B[j] % MOD) % MOD * ((x[j + 1] - x[j]) % MOD);
      ans %= MOD;
    }
    cout << ans << endl;
  }
}