Python设置相邻字母的组合

Question

I have a sequence of letters and want to find all combinations of letters possible by cutting off the letters around a certain letter.

C is my special letter here and X can be anything, so with a sequence:

XCXX

So all the possible combinations would be:

XCXX
XCX
XC
CXX
CX
C

Is there a python function for this, or should I code it from scratch?

Thank you

Answer 1

I would have coded it from scratch like this:

def cuts(s,i): 
   return [ s[a:b] for a in range(i+1) for b in range(i+1,len(s)+1)]

where s is the string and i is the index of your "special letter" in s . Example:

>>> cuts('XCXX', 1)
['XC', 'XCX', 'XCXX', 'C', 'CX', 'CXX']

Answer 2

Try counting the number of elements before and after your special element C . Then your combinations are uniquely defined by those two numbers, and you can just use string slicing to get a specific one.

Answer 3

No, but you could do it as a one-liner.

data = "XCXX"
cIndex = data.index("C")
permutations = [data[i:j+1] for i in range(cIndex+1) 
        for j in range(cIndex, len(data))]