PythonProblemSolving/Permutation.py at master · ebaumstarck/PythonProblemSolving · GitHub

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'''
given a string, return all the permutations
based on the characters of the string
'''
defPermutationStr(string, chars_stack=None, used_chars=None):
ifchars_stackisNone:
chars_stack= []
ifused_charsisNone:
used_chars= [Falsefor_inrange(len(string))]
ifall(used_chars):
yield"".join(chars_stack)
else:
foriinrange(len(string)):
ifnotused_chars[i]:
used_chars[i] =True
chars_stack.append(string[i])
forstring1inPermutationStr(string,
chars_stack=chars_stack,
used_chars=used_chars):
yieldstring1
used_chars[i] =False
chars_stack.pop()

forperminPermutationStr("abcd"):
printperm

defPermutation1(string):
out= []
used= [Falseforxinstring]
Permute(string, out, used)

defPermute(string,out,used):
iflen(out) ==len(string) :
print"> %s"%"".join(out)
return
foriinrange(len(string)):
ifused[i]:
continue
out.append(string[i])
used[i] =True
Permute(string, out, used)
used[i] =False
out.pop()

Permutation1('erty')

forain [1,2,3]:
forbin ['a','b','c']:
forcin [10,11,12]:
fordin ['z', 'y', 'x']:
forein ['q', 'r', 't']:
printa, b, c, d, e

arrays= [
 [1,2,3],
 ['a','b','c'],
 [10,11,12],
 ['z', 'y', 'x'],
 ['q', 'r', 't'],
 [3, 4, 5]
]