Extended use of Python slices (slice)

#-*-Coding:utf-8-*-__author__ = ' xy ' #切片 (slice) Extension Usage # # # # of slices with a step index to expand # Slice[1:2:3] where the 3rd position represents the step size, the default is # Simple str flip: s = ' ABCDE ' Print s[::-1]# >>> ' EDCBA ' #间隔一个字符取值: Print s[::2]# >>> ' ace ' #2 Slice index does not cross print (' A ', ' B ', ' C ') [- 100:100]# >>> (' A ', ' B ', ' C ') #3 [None] enhancements to the FOR loop: #每次循环把最后一个字符干掉: s = ' abcde ' i = -1for i in range ( -1, Len (s),-1): 
  
   print s[:i]# >>># abcd# abc# ab# a# If you want to complete output ' ABCDE ' for the first time, you generally need to add a print statement to the for front # see the following improvements: s = ' abcde ' for i in [none]+ Range ( -1,-len (s),-1):    print s[:i]# >>># abcde# abcd# abc# ab# A
  

Extended use of Python slices (slice)