Python输出由1,2,3,4组成的互不相同且无重复的三位数

#!/usr/bin/python
# -*- coding: UTF-8 -*-
 
for i in range(1,5):
 for j in range(1,5):
  for k in range(1,5):
   if( i != k ) and (i != j) and (j != k):
    print i,j,k

#!/usr/bin/env python
#-*- coding:utf-8 -*-

import pprint

list_num = ['1','2','3','4']
list_result = []
for i in list_num:
 for j in list_num:
  for k in list_num:
   if len(set(i + j + k)) == 3:
    list_result += [int(i + j + k)]
print("能组成%d个互不相同且无重复数字的三位数："%len(list_result))
pprint.pprint(list_result)