Solution: Flip Game
Understand how to solve the Flip Game problem by exploring backtracking concepts focused on generating all valid next states. Learn to identify consecutive '++' pairs in a string, flip them to '--', and systematically produce all possible next game states. This lesson helps you implement enumeration of moves without in-place changes, analyze time and space complexity, and apply these skills to similar backtracking problems.
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Statement
You are playing a Flip Game with a friend.
You are given a string currentState consisting only of the characters '+' and '-'. Players take turns flipping two consecutive "++" into "--". The game ends when a player cannot make a move, at which point the other player wins.
Return all possible states of currentState after performing exactly one valid move. The answer may be returned in any order. If no valid move exists, return an empty list.
Constraints:
currentState.lengthcurrentState[i]is either'+'or'-'
Solution
The main idea is to generate all possible valid next moves by ...