python练习题：实现四个组成不相同且无重复的三位数

题目：有四个数字：1、2、3、4，能组成多少个互不相同且无重复数字的三位数？各是多少？

for i in range(1,5):
    for j in range(1,5):
        for k in range(1,5):
            if(i !=j) and (i !=k) and (j !=k):
                print(i,j,k)

实现结果：

C:\Anaconda3\python.exe "C:\Program Files\JetBrains\PyCharm 2019.1.1\helpers\pydev\pydevconsole.py" --mode=client --port=56955
import sys; print('Python %s on %s' % (sys.version, sys.platform))
sys.path.extend(['C:\\app\\PycharmProjects', 'C:/app/PycharmProjects'])
Python 3.7.6 (default, Jan  8 2020, 20:23:39) [MSC v.1916 64 bit (AMD64)]
Type 'copyright', 'credits' or 'license' for more information
IPython 7.12.0 -- An enhanced Interactive Python. Type '?' for help.
PyDev console: using IPython 7.12.0
Python 3.7.6 (default, Jan  8 2020, 20:23:39) [MSC v.1916 64 bit (AMD64)] on win32
runfile('C:/app/PycharmProjects/tensorflow/test.py', wdir='C:/app/PycharmProjects/tensorflow')
1 2 3
1 2 4
1 3 2
1 3 4
1 4 2
1 4 3
2 1 3
2 1 4
2 3 1
2 3 4
2 4 1
2 4 3
3 1 2
3 1 4
3 2 1
3 2 4
3 4 1
3 4 2
4 1 2
4 1 3
4 2 1
4 2 3
4 3 1
4 3 2

拓展：有四个数字：1、2、3、4，能组成多少个互不相同且无重复数字的四位数？各是多少？

'''
遇到问题没人解答？小编创建了一个Python学习交流QQ群：778463939
寻找有志同道合的小伙伴，互帮互助,群里还有不错的视频学习教程和PDF电子书！
'''
for i in range(1,5):
    for j in range(1,5):
        for k in range(1,5):
            for m in range(1,5):
                if (i != k) and (i != j) and (i != m) and (j != k) and (j != m) and (k != m):
                    print(i,j,k,m)

实现结果：

C:\Anaconda3\python.exe "C:\Program Files\JetBrains\PyCharm 2019.1.1\helpers\pydev\pydevconsole.py" --mode=client --port=57179
import sys; print('Python %s on %s' % (sys.version, sys.platform))
sys.path.extend(['C:\\app\\PycharmProjects', 'C:/app/PycharmProjects'])
Python 3.7.6 (default, Jan  8 2020, 20:23:39) [MSC v.1916 64 bit (AMD64)]
Type 'copyright', 'credits' or 'license' for more information
IPython 7.12.0 -- An enhanced Interactive Python. Type '?' for help.
PyDev console: using IPython 7.12.0
Python 3.7.6 (default, Jan  8 2020, 20:23:39) [MSC v.1916 64 bit (AMD64)] on win32
runfile('C:/app/PycharmProjects/tensorflow/test.py', wdir='C:/app/PycharmProjects/tensorflow')
1 2 3 4
1 2 4 3
1 3 2 4
1 3 4 2
1 4 2 3
1 4 3 2
2 1 3 4
2 1 4 3
2 3 1 4
2 3 4 1
2 4 1 3
2 4 3 1
3 1 2 4
3 1 4 2
3 2 1 4
3 2 4 1
3 4 1 2
3 4 2 1
4 1 2 3
4 1 3 2
4 2 1 3
4 2 3 1
4 3 1 2
4 3 2 1