T = int(input())

def calc(l,r):
    if r - l <= 10:
        ans = 0
        for i in range(l,r + 1):
            for j in range(i,r + 1):
                if i + j > l + r:continue
                ans ^= (i + j)
        return ans
    
    u = (r - l) // 4
    if (u - 1) % 2 == 0:
        ans = 1
    else:
        ans = 0
    for j in range(2 * l + 4 * u,l + r + 1):
        ans ^= j
    for j in range(2 * l + 4 * u + 2,l + r + 1):
        ans ^= j
    return ans
for _ in range(T):
    l,r = map(int,input().split())
    print(calc(l,r))