更新时间:2023-02-05 13:36:52
你发的两行都很好,但是你可以纯整数做,效率最高:
Both lines you posted are fine, but you can do it purely in integers, and it will be the most efficient:
def sum_digits(n):
s = 0
while n:
s += n % 10
n //= 10
return s
或使用 divmod
:
def sum_digits2(n):
s = 0
while n:
n, remainder = divmod(n, 10)
s += remainder
return s
没有增加分配的版本更快:
Even faster is the version without augmented assignments:
def sum_digits3(n):
r = 0
while n:
r, n = r + n % 10, n // 10
return r
> %timeit sum_digits(n)
1000000 loops, best of 3: 574 ns per loop
> %timeit sum_digits2(n)
1000000 loops, best of 3: 716 ns per loop
> %timeit sum_digits3(n)
1000000 loops, best of 3: 479 ns per loop
> %timeit sum(map(int, str(n)))
1000000 loops, best of 3: 1.42 us per loop
> %timeit sum([int(digit) for digit in str(n)])
100000 loops, best of 3: 1.52 us per loop
> %timeit sum(int(digit) for digit in str(n))
100000 loops, best of 3: 2.04 us per loop