Question:
How can I generate a list of all combinations of digits in a four digit number?
The first digit can contain 0. There are 4 digits, each can contain a number from 0 to 9. As I understand it, this is 10^4 .
How can this be implemented?
Answer:
If you're not smart, then you just need to print the string representation of numbers up to 9999 with leading zeros:
for i in range(10000):
print('{:04d}'.format(i))