用指定的数字制作所有数字，python

Question

in python, I want to get all n-digit numbers with digits 1 to n (n <10, each exactly once). How can I ??

Can similar things be done? thanks

Answer 1

You can use itertools.permutations() to get the digits of each number, and then use map() with str() and int() to turn the generated digits into the desired numbers:

import itertools

n = 3
for item in itertools.permutations(range(1, n + 1), n):
    result = int(''.join(map(str, item)))
    print(result)

This outputs (only first three / last three lines shown):

123
132
213
231
312
321

Answer 2

Just use itertools.permutations

import itertools

n = 3
for item in itertools.permutations(range(1, n + 1), n):
    print(*item, sep='')
    # In case you want to do something with the integer value:
    result = int(''.join(map(str, item)))

Output:

123
132
213
231
312
321