How to Iterate Over String using next?

Question

There's a string:

x = '012846871'

how would I loop so it would give me how many 1's are in the string:

010000001

as in like x[0] has no 1's, x[1] has one 1 and so on.

Answer 1

You can use generator expression, for example something like this should work:

x = '012846871'
mask = ''.join('1' if digit == '1' else '0' for digit in x)
print(mask)

>>> 010000001