python - Python中双循环中所有字符串的大写

Question

我有以下 Python 代码，它循环遍历字符串并将每个字符大写:

str = 'abcd'
l  = list(str)
for i in range(len(l)):
    rl = list(str)
    cap_char = l[i].capitalize()
    rl[i] = cap_char
    str1 = ''.join(rl)
    print str1

产生:

Abcd aBcd abCd abcD

我想增强此代码以增加受大写限制的连续字符的数量，直到该数字达到 len(l) - 1 以生成:

Abcd aBcd abCd abcD    >> - 1 char capitalized
ABcd aBCd abCD AbcD    >> - 2 chars capitalized
ABCd aBCD AbCD ABcD    >> - 3 chars capitalized

我在进行索引运算时遇到“索引超出范围”错误，理解 idices 应该换行，但似乎无法生成优雅的代码；(

Answer 1

import itertools
x = 'abcd'
n = len(x)
for i in xrange(1,n):
  combinations = itertools.combinations(range(n), i)
  for c in combinations:
    print ''.join([k if m not in c else k.upper() for m,k in enumerate(x)]),
  print '    >> - {0} char(s) capitalized'.format(i)

输出:

Abcd aBcd abCd abcD     >> - 1 char(s) capitalized
ABcd AbCd AbcD aBCd aBcD abCD     >> - 2 char(s) capitalized
ABCd ABcD AbCD aBCD     >> - 3 char(s) capitalized