Stone Game

Initially, Alice and Bob both have a bag of $N$ stones each with every stone having a **lowercase alphabet** written on it. Both players know the stones of the other player. Alice and Bob want to create a string $S$ of length $2 \cdot N$ using the stones they have. They play a game to create the string. The rules of the game are as follows: - Initially, all the indices of $S$ are empty. - Alice