Each prawn, new to python soon, could you tell me how to write the above logic?
Abcd for b and d, use the abcd circulation substitution, total cycle N layer, N
Law of the character after the sorting,
For example, the first layer is the abcd
The second will b and d are replaced by the abcd, get aabcdcabcd
As the third layer is to replace b and d with the abcd (no matter how many layers, both for the abcd), get aaabcdcaabcdcabcd
By analogy, to N layer only,

CodePudding user response:

Cycle the

 n=3 
S='abcd' 
While n & gt; 0: 
S=re. Sub (' [bd] ', 'abcd' s) 
N -=1