Slightly Functional Game of Life

slightly-functional-conways-game-of-life.js

function boardGet(arr, i, j) {
  if (i < 0 || j < 0 || i >= arr.length || j >= arr[i].length) {
    return 0
  }
  return arr[i][j]
}

function countNeighbors(board, i, j) {
  return (
    boardGet(board, i - 1, j - 1) +
    boardGet(board, i - 1, j) +
    boardGet(board, i - 1, j + 1) +
    boardGet(board, i, j - 1) +
    boardGet(board, i, j + 1) +
    boardGet(board, i + 1, j - 1) +
    boardGet(board, i + 1, j) +
    boardGet(board, i + 1, j + 1)
  )
}

function isAlive(cell) {
  return cell === 1
}

function shouldSurvive(cell, neighbors) {
  if(isAlive(cell) && neighbors === 2 || neighbors === 3) return 1
  if(!isAlive(cell) && neighbors === 3) return 1
  return 0
}

function conwaysGameOfLife(board) {
  return board.map((row, i) => row.map((cell, j) => shouldSurvive(cell, countNeighbors(board, i, j))))
}

var board = Array.from({ length: 50 }, () =>
  Array.from({ length: 50 }, () => Math.round(Math.random()))
)

;(async () => {
  let x = 1000
  for (let i = 0; i < x; i++) {
    console.clear()
    board = conwaysGameOfLife(board)
    console.log(board.map((i) => i.join(" ")).join("\n"))
    await new Promise((resolve) => setTimeout(resolve, 50))
  }
})()