在产生一定数量后如何打破循环？

Question

So here is my code, I have created this program so that it will run in a loop until either DIGITS 1 and 4 occur in the output, which will then break, but I want to change it in a way so that instead of "break" after either digits 1 or 4 are detected, I want it to break only after the output yields 1 or 4, how can I do that?? Here is my code..

what should I do to make sure it stops when the output itself, not the DIGITS in the output, the output itself, yields either 1 or 4?

Answer 1

You can just loop over and over and check the entire sum_of_digits . Try this:

number = 145
sum_of_digits = 0
x = ''
while x not in ['1', '4']:
    for digit in str(number):
       sum_of_digits += (int(digit)**2)
    x = str(sum_of_digits)
    number = sum_of_digits
    sum_of_digits = 0
print(x)

my output: 4

This can be improved but I didn't want to change much more of your code