let arr = new Array(cols);

  for(let i = 0; i < arr.length; i++){

    arr[i] = new Array(rows);

    for(let j = 0; j < arr[i].length; j++){

      arr[i][j] = 0;

    }

  }

  return arr;

}

​

let w;

let grid;

let nextGrid;

let neighbors;

let cols, rows;

let state;

let rule;

let nb;

​

function setup() {

  createCanvas(900, 900);

  w = 3;

  cols = width / w;

  rows = height / w;

  grid = make2DArray(cols, rows);

  // for(i = 0; i < rows; i++){

  //   for(j = 0; j < cols; j++){

  //     grid[i][j] = floor(random(2));

  //   }

  // }

  rule = [1, 0, 0, 1, 0, 0, 1, 1]

  neighbors = [];

  noStroke();

}

​

function draw() {

  background(220);

  nextGrid = grid;

  // for(i = 0; i < rows; i++){

  //     for(j = 0; j < cols; j++){

  //       state = grid[i][j];

  //       fill(state * 100);

  //       rect(i * w, j * w, w);

  //     }

  // }

  // if(frameCount % 10 == true){

    for(i = 0; i < rows; i++){

      for(j = 0; j < cols; j++){

        state = grid[i][j];

​

        fill(state * 100);        

        rect(i * w, j * w, w);

        if(i > 0 && i < rows - 1){

          neighbors[0] = grid[i - 1][j];

          neighbors[1] = grid[i][j];

          neighbors[2] = grid[i + 1][j];

        } else if(i == 0 && j > 0){

          neighbors[0] = grid[i][j - 1];

          neighbors[1] = grid[i][j];

          neighbors[2] = grid[i + 1][j];

        } else if(i == 0 && j == 0){

          neighbors[0] = grid[rows - 1][cols - 1];

          neighbors[1] = grid[i][j];

          neighbors[2] = grid[i + 1][j];

        } else if(i == rows - 1 && j > 0){

          neighbors[2] = grid[i][j - 1];

          neighbors[0] = grid[i - 1][j];

          neighbors[1] = grid[i][j];

        } else if(i == rows - 1 && j == 0){

          neighbors[2] = grid[0][j + 1];

          neighbors[0] = grid[i - 1][j];

          neighbors[1] = grid[i][j];

        }

​

        if(neighbors[0] == 0 && neighbors[1] == 0 && neighbors[2] == 0) {

          nextGrid[i][j] = 1;

        }

        if(neighbors[0] == 0 && neighbors[1] == 0 && neighbors[2] == 1) {

          nextGrid[i][j] = 0;

        }

        if(neighbors[0] == 0 && neighbors[1] == 1 && neighbors[2] == 1) {

          nextGrid[i][j] = 1;

        }

        if(neighbors[0] == 1 && neighbors[1] == 1 && neighbors[2] == 1) {

          nextGrid[i][j] = 0;

        }

        if(neighbors[0] == 1 && neighbors[1] == 0 && neighbors[2] == 1) {

          nextGrid[i][j] = 1;

        }

        if(neighbors[0] == 1 && neighbors[1] == 1 && neighbors[2] == 0) {

          nextGrid[i][j] = 0;

        }

        if(neighbors[0] == 1 && neighbors[1] == 0 && neighbors[2] == 0) {

          nextGrid[i][j] = 1;

        }

        if(neighbors[0] == 0 && neighbors[1] == 1 && neighbors[2] == 0) {

          nextGrid[i][j] = 0;

        }

      }

    }

  // }

  grid = nextGrid;

}