计算w/o将整数转换为字符串的位数:

x=123
x=abs(x)
i = 0
while x >= 10**i:
    i +=1
# i is the number of digits

对于子孙后代来说，这无疑是迄今为止解决这个问题最慢的方法:

def num_digits(num, number_of_calls=1):
    "Returns the number of digits of an integer num."
    if num == 0 or num == -1:
        return 1 if number_of_calls == 1 else 0
    else:
        return 1 + num_digits(num/10, number_of_calls+1)

def digits(n)
    count = 0
    if n == 0:
        return 1
    
    if n < 0:
        n *= -1

    while (n >= 10**count):
        count += 1
        n += n%10

    return count

print(digits(25))   # Should print 2
print(digits(144))  # Should print 3
print(digits(1000)) # Should print 4
print(digits(0))    # Should print 1

没有导入和str()这样的函数的解决方案

def numlen(num):
    result = 1
    divider = 10
    while num % divider != num:
        divider *= 10
        result += 1
    return result

>>> a=12345
>>> a.__str__().__len__()
5

您可以使用以下解决方案:

n = input("Enter number: ")
print(len(n))
n = int(n)