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Copy path1.1：字符的移动.py
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1.1：字符的移动.py
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# -*- coding: utf-8 -*-
import copy
# 整体函数接口说明：
#
# Args:
# s: 给定需要移位的list
# m: 需要移动的位数
#
# Returns:
# 无。直接修改传入的list
#
# Author:
# Jasonwbw([email protected])
##########################################################################
# Tools
def left_shift_one(s, i, j):
'''s从i(包含)到j(不包含)，左移一位
Author: Jasonwbw([email protected])
Editor:
Args:
s : 给定需要移位的list
i : 索引位置i
j : 索引位置j
'''
t = s[i]
for k in xrange(i, j - 1):
s[k] = s[k + 1]
s[j - 1] = t
##########################################################################
# 思路零
# python语言基础思路
def simple_shift(s, m):
'''python对于list类型的s,最适合的暴力方法是直接选取两部分的字符串直接拼接
Author:Jasonwbw([email protected])
Editor:
'''
if m < 0:
raise Exception('m is less than 0')
if len(s) <= m:
m = m % len(s)
t = copy.copy(s)
del s[:]
s += t[m:] + t[:m]
##########################################################################
# 思路一
# see https://github.com/julycoding/The-Art-Of-Programming-By-July/blob/master/ebook/zh/01.0.md#%E6%80%9D%E8%B7%AF%E4%B8%80%E6%9A%B4%E5%8A%9B%E7%A7%BB%E4%BD%8D%E6%B3%95
def left_shift(s, m):
'''循环m次左移1位
Author: Jasonwbw([email protected])
Editor:
'''
if m < 0:
raise Exception('m is less than 0')
else:
m = m % len(s)
for i in xrange(m):
left_shift_one(s, 0, len(s))
##########################################################################
# 思路二
# see https://github.com/julycoding/The-Art-Of-Programming-By-July/blob/master/ebook/zh/01.0.md#%E6%80%9D%E8%B7%AF%E4%BA%8C%E4%B8%89%E6%AD%A5%E7%BF%BB%E8%BD%AC%E6%B3%95
def invert(s, start, end):
'''Invert the list s from start to end(contained).
Author: Jasonwbw([email protected])
Editor:
Args:
s : 要翻转的list
start : 翻转的起始位置
end : 翻转的结束位置(包含)
'''
n = end - start + 1
for i in xrange(n / 2):
s[start + i], s[end - i] = s[end - i], s[start +i]
def invert_solution(s, m):
'''
Author: Jasonwbw([email protected])
Editor:
'''
n = len(s)
invert(s, 0, m - 1)
invert(s, m, n - 1)
invert(s, 0, n - 1)
##########################################################################
if __name__ == '__main__':
a1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i']
a2 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']
a3 = ['a', 'b', 'c', 'd', 'e', 'f', 'g']
a0_1 = copy.copy(a1)
a0_2 = copy.copy(a2)
a0_3 = copy.copy(a3)
simple_shift(a0_1, 3)
simple_shift(a0_2, 3)
simple_shift(a0_3, 3)
print 'simple_shift:'
print a0_1
print a0_2
print a0_3
print
a1_1 = copy.copy(a1)
a1_2 = copy.copy(a2)
a1_3 = copy.copy(a3)
left_shift(a1_1, 3)
left_shift(a1_2, 3)
left_shift(a1_3, 3)
print 'left_shift:'
print a1_1
print a1_2
print a1_3
print
a2_1 = copy.copy(a1)
a2_2 = copy.copy(a2)
a2_3 = copy.copy(a3)
invert_solution(a2_1, 3)
invert_solution(a2_2, 3)
invert_solution(a2_3, 3)
print 'invert_solution:'
print a2_1
print a2_2
print a2_3
print