pacman/exercises/25/pacman_ai/README.md

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Exercise: PacMan AI

Let's implement a naive AI for PacMan.

Background: PacMan Moves

At each intersection, check if there is a ghost directly inline with that path. If the path is free of ghosts, you are allowed to turn there. And if PacMan is moving in a direction, and a ghost enters his path, then pacman will reverse.

For example if pacman is at an intersection and can go either right or up, and there is a ghost in the path going right, then pacman will go up. Then while pacman is going up, a ghost enters that path, pacman will go back.

You only need to worry about the grid itself and any ghosts on the North/South/East/West axis of PacMan.

Exercise

1. Implement PacManAI::pelletClosestToPacman and test your implementation with the test in testPacmanAI.cpp called "Find pellet closest to pacman"

The function should return the position of the pellet that is "closest" to PacMan. One implementation could be to sort the vector of pellets by the distance they have to PacMan, and then return the first one.

Hint 1: use the positionDistance function to find the distance to PacMan Hint 2: use the std::sort function to sort the vector

GridPosition PacManAI::pelletClosestToPacman(GridPosition pacmanGridPosition,
                                             std::vector<GridPosition> & pellets) {
  return {0, 0};
}

2. Implement PacManAI::isValidMove and test your implementation with the test in testPacmanAI.cpp called "Is valid move"

Hint:

bool PacManAI::isValidMove(const Move & move) {
  return false;
}

3. Implement PacManAI::optimalDirection and test your implementation with the test in testPacmanAI.cpp called "Is optimal direction"

Hint:

Direction PacManAI::optimalDirection(const std::array<Move, 4> & moves) {
  return Direction::NONE;
}