def f(n,x):
    q,r = divmod(max(x,0),n-1)
    return (2*r+2+(n-1)*(q-1))*q//2
def g(n,m,x): return f(n,x)-f(n,x-m-1)
for _ in range(int(input())):
    n,m,l,r = map(int,input().split())
    print((g(n,m,r)-g(n,m,l-1)+g(n,m,m-l)-g(n,m,m-r-1)+max(min(m,r)-l+1,0))%998244353)