from sys import stdin
input = stdin.readline
MOD = 998244353
def f(r, n):
    r1, r2 = r // n, r % n
    ans = r1 * (r2 + 1) + n * (r1 - 1) * r1 // 2
    return ans % MOD
def main():
    n, m, l, r = map(int, input().split())
    n -= 1
    m += 1
    l -= 1
    ans = 0
    ans += f(r, n) - f(l, n)
    ans -= f(r - m, n) - f(l - m, n)
    print(ans % MOD)
for _ in range(int(input())):
    main()