def calc(n, X, Y):
    x = -(-X // n) * n
    y = Y // n * n
    if x > y:
        return (Y - X + 1) * (Y // n)
    else:
        tmp = (x - X) * (X // n)
        tmp += (Y - y + 1) * (Y // n)
        tmp += (y - x) * (x // n + (y - 1) // n) // 2
        return tmp % MOD


def solve(n, m, l, r):
    N1 = n - 1
    ans1 = r - l + 1
    ans2 = calc(N1, l, r)
    ans3 = calc(N1, m - r, m - l)
    ans = ans1 + ans2 + ans3
    ans %= MOD
    return ans

MOD = 998244353
T = int(input())
for t in range(T):
    N, M, L, R = map(int, input().split())
    print(solve(N,M,L,R))

'''
N = 3
N1 = N - 1
M = 10
for l in range(11):
    for r in range(l, 11):
        tmp1 = r - l + 1
        tmp2 = 0
        tmp3 = 0
        for i in range(l, r + 1):
            tmp2 += i // N1
            tmp3 += (M - i) // N1
        tmp = tmp1 + tmp2 + tmp3
        a = solve(N, M, l, r)
        print(l, r, " ", *a, " ", tmp, tmp1, tmp2, tmp3)
'''