Display number with leading zeros.

Question

Given:

a = 1

b = 10

c = 100

I want to display a leading zero for all numbers with less than 2 digits.

Essentially displaying

01

10

100

Answer 1

x = [1, 10, 100]
for i in x:
    print '%02d' % i

results:

01
10
100

Read more information about string formatting using % in the documentation.

Answer 2

Here you are:

print "%02d" % (1,)

Basically % is like printf or sprintf.

Answer 3

Use a format string - http://docs.python.org/lib/typesseq-strings.html

For example:

python -c 'print "%(num)02d" % {"num":5}'

Answer 4

In Python 3.0 you would use the format() string method:

for i in (1, 10, 100):
    print('{num:02d}'.format(num=i))

or using the built-in (for a single number):

print(format(i, '02d'))

See the PEP-3101 documentation for the new formatting functions.

Answer 5

You can use zfill:

print str(1).zfill(2) 
print str(10).zfill(2) 
print str(100).zfill(2) 

prints:

01
10
100