def f(x, N):
	if x == -1:
		return 0
	q = x // (N - 1)
	r = x % (N - 1)
	return (N - 1) * q * (q - 1) // 2 + q * (r + 1)

def solve(N, M, L, R):
	return f(R, N) - f(L - 1, N) + f(M - L, N) - f(M - R - 1, N) + R - L + 1

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