python切片的步进、添加、连接简单操作示例

#coding:utf-8
a="123456"
print a[::-1]
#output 654321
print a[::-2]
#output 642
print a[::2]
#output 135

#coding:utf-8
a='123456789'
a1=[]
a1.extend(a[0:4])
a1.extend(a[4:])
print a1
#output ['1', '2', '3', '4', '5', '6', '7', '8', '9']

#coding:utf-8
__author__ = 'Administrator'
import string
a='python is nice'
b='mengtianwxs is a good boy'
print a[:6]+' and '+b[:11]
#output python and mengtianwxs