// Constants
const CELL_COUNT = ROWS * COLUMNS;
const COLORS = ['#222', '#ffee32'];

let cells = new Array(CELL_COUNT).fill(0);
cells[0] = 1;

function setup() {
  // Setup boilerplate
  renderCells();
}

function renderCells() {
  let left = PADDING;
  let top = PADDING;
  let leftEnd = left + COLUMNS * CELL_SIZE;
  for (let i = 0; i < cells.length; i++) {
    fill(COLORS[cells[i]]);
    let size = CELL_SIZE - 2;
    rect(left, top, size, size);

    left += CELL_SIZE;
    if (left === leftEnd) {
      left = PADDING;
      top += CELL_SIZE;
    }
  }
}
Grid-1-3
