.* v.s. .*?

1, .*

Code:

import re

str = 'a111a222a'
pattern = re.compile('a.*a')
items = re.findall(pattern, str)
for item in items
    print item

output: a111a222a

2, .*?

Code 1

import re

str = 'a111a222a'
pattern = re.compile('a(.*?)a')
items = re.findall(pattern, str)
for item in items:
    print item

output: 111

Code 2

pattern = re.compile('a(.*?)a')
str = 'a111a222a333a'
items = re.findall(pattern, str)
for item in items:
    print item

output: 111 , 333