import sys
input = sys.stdin.readline

# https://qiita.com/AkariLuminous/items/3e2c80baa6d5e6f3abe9#4-floor_sum
def floor_sum(n, m, a, b=0):
    ans = 0
    while True:
        if a >= m or a < 0:
            ans += n * (n - 1) * (a // m) // 2
            a %= m
        if b >= m or b < 0:
            ans += n * (b // m)
            b %= m
        y_max = a * n + b
        if y_max < m: break
        n, b, m, a = y_max // m, y_max % m, a, m
    return ans


T = int(input())
mod = 998244353
for _ in range(T):
    N, M, L, R = map(int, input().split())
    ans = M + 1 + floor_sum(M + 1, N - 1, -1, R) - floor_sum(M + 1, N - 1, -1, L + N - 2)
    print(ans % mod)