Question

How do I display a leading zero for all numbers with less than two digits?

1    →  01 10   →  10 100  →  100 

Answer 1

In Python 2 (and Python 3) you can do:

number = 1 print("%02d" % (number,)) 

Basically % is like printf or sprintf (see docs).

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For Python 3.+, the same behavior can also be achieved with format:

number = 1 print("{:02d}".format(number)) 

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For Python 3.6+ the same behavior can be achieved with f-strings:

number = 1 print(f"{number:02d}")