#Game of Life The Game of Life is a cellular automation game with a very limited set of principles and rules. Despite its simplicity it allows a variety of different implementations.

This implementation is based on the idea, that a Cell, which could be dead or alive, is aware of all other Cells surrounding itself (=neighbors):

class Cell(var isAlive : Boolean = false) {
    val neighbors: MutableList<Cell> = arrayListOf()
}

With this design a Cell is capable of evolving itself. So the few following lines represent the complete set of Conway's rules:

fun evolve(livingNeighborsCount: Int =
            neighbors.count { it.isAlive }) {
        isAlive = when(livingNeighborsCount) { 
            0, 1 -> false
            2 -> isAlive
            3 -> true
            else -> false
        }
    }

Since the Game of Life is not about a single Cell but about a bunch of Cells this implementation also consists of an Universe, which contains all Cells and is responsible for triggering the evolution of all Cells:

class Universe(val size: Int) {
    val cells = Array(size * size, { Cell() })

    fun evolve() {
        val livingNeighborCounts = cells.map { it.neighbors.count { it.isAlive } }
        cells.forEachIndexed { i, cell -> cell.evolve(livingNeighborCounts[i]) }
    }
}