Buggy python submission (verdict: Runtime Error):
a, b = map(int, input().split())
A = str(bin(a))[2:]
B = str(bin(b))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = str(bin(int(A[:-1], 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        mae = str(bin(int(A[:-1], 2)^int(B[:-1], 2)))[2:]
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))


Fixed submission:
a, b = map(int, input().split())
A = str(bin(a))[2:]
B = str(bin(b))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        mae = str(bin(int(c, 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        if b <= 1:
            d = '0'
        else:
            d = B[:-1]

        mae = str(bin(int(c, 2)^int(d, 2)))[2:]
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))

Buggy python submission (verdict: Runtime Error):
a, b = map(int, input().split())
A = str(bin(a))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = str(bin(int(A[:-1], 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 2 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))


Fixed submission:
a, b = map(int, input().split())
A = str(bin(a))[2:]
B = str(bin(b))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        mae = str(bin(int(c, 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        if b <= 1:
            d = '0'
        else:
            d = B[:-1]

        mae = str(bin(int(c, 2)^int(d, 2)))[2:]
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))

Buggy python submission (verdict: Runtime Error):
a, b = map(int, input().split())
A = str(bin(a))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = str(bin(int(A[:-1], 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))


Fixed submission:
a, b = map(int, input().split())
A = str(bin(a))[2:]
B = str(bin(b))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        mae = str(bin(int(c, 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        if b <= 1:
            d = '0'
        else:
            d = B[:-1]

        mae = str(bin(int(c, 2)^int(d, 2)))[2:]
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))

Buggy python submission (verdict: Runtime Error):
a, b = map(int, input().split())
A = str(bin(a))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = str(bin(int(A[:-1], 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        mae = str(bin(int(A[:-1], 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))


Fixed submission:
a, b = map(int, input().split())
A = str(bin(a))[2:]
B = str(bin(b))[2:]
if A[-1] == '0':
    if (b-a+1)%2 == 0:
        mae = '0'
    else:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        mae = str(bin(int(c, 2)+int((b-a)/2)))[2:]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 1:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))
else:
    if (b-a+1)%2 == 0:
        if a <= 1:
            c = '0'
        else:
            c = A[:-1]
        if b <= 1:
            d = '0'
        else:
            d = B[:-1]

        mae = str(bin(int(c, 2)^int(d, 2)))[2:]
    else:
        mae = A[:-1]
    if (b-a+1)%4 == 0 or (b-a+1)%4 == 3:
        print(int(mae+'0', 2))
    else:
        print(int(mae+'1', 2))