I wanted to add in list years from 0000 to 9999, what I did:
i = 0
a = []
while i <= 9:
a += [i]
i += 1
years = []
for i1 in a:
for i2 in a:
for i3 in a:
for i4 in a:
numbers = f'{i1}{i2}{i3}{i4}'
years += [numbers]
But what if I need do this 99 times? Is exist any way to do this without simple copypasting code?
What you want is called a *cartesian product.
from itertools import product
for numbers in product([1,2,3], repeat=5): ...
However, this increases exponentially with the number of loops, and you should probably rethink what you're trying to do.
This uses the zfill function to fill the rest of the left portion with zeros for a string . for n = 2 it prints from 00 to 99 which is shown below and for n = 4 it produces the same output as your program.
output = []
n=2
for i in xrange(0,10**n):
output.append(str(i).zfill(n))
print(output)
OUTPUT
['00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32', '33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43', '44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54', '55', '56', '57', '58', '59', '60', '61', '62', '63', '64', '65', '66', '67', '68', '69', '70', '71', '72', '73', '74', '75', '76', '77', '78', '79', '80', '81', '82', '83', '84', '85', '86', '87', '88', '89', '90', '91', '92', '93', '94', '95', '96', '97', '98', '99']
["{:04}".format(i) for i in range(10000)], It will create a list of list with numbers represented as strings from 0000 to 9999. if you want 99 such lists, there's may ways to do it. One of them is to create a list of lists.[["{:04}".format(i) for i in range(10000)] for i in range(99)]