You are playing the following Flip Game with your friend: Given a string that contains only these two characters: + and -, you and your friend take turns to flip two consecutive “++” into “–“. The game ends when a person can no longer make a move and therefore the other person will be the winner.
Write a function to compute all possible states of the string after one valid move.
For example, given s = “
++“, after one move, it may become one of the following states:
[ "--++", "+--+", "++--" ]
If there is no valid move, return an empty list .
Credits To: leetcode.com
Leave me comments, if you have better ways to solve.
## Blog link: https://code.dennyzhang.com/flip-game ## Basic Ideas: One pass ## Complexity: Time O(n), Space O(1) class Solution: def generatePossibleNextMoves(self, s): """ :type s: str :rtype: List[str] """ res =  for i in range(1, len(s)): if s[i-1:i+1] == '++': res.append(s[:i-1] + '--' + s[i+1:]) return res