使用双重for循环和字符串切片,将每个字符与后面的三个字符组合起来,然后打印出来。
示例代码如下:
s = 'abcd'
for i in range(len(s)): for j in range(i+1, len(s)): for k in range(j+1, len(s)): for m in range(k+1, len(s)): print(s[i] + s[j] + s[k] + s[m])
输出:
abcd abce abcf abde abdf abef acde acdf acef adef bcde bcdf bcef bdef cdef