let TERMS = 2;

let count = [];

​

function setup() {

  createCanvas(400, 400);

  for (let i = 0; i < 2 * CHOICES; i++) {

    count.push(0);

  }

  drawRandom();

}

​

function draw() {

  background(255);

  let maxY = max(count);

​

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

    let x = i * (width / count.length);

    let h = map(count[i], 0, maxY, 0, -height);

    let c = map(count[i], maxY / 4, maxY, 0, 255, true);

​

    fill(c, 0, 255 - c);

    rect(x, height, width / count.length, h);

  }

}

​

function drawRandom() {

  for (let i = 0; i < 500; i++) {

    let y = 0;

    for (let c = 0; c < TERMS; c++) {

      y += floor(random(CHOICES));

    }

    count[y] = count[y] + 1;

  }

}

​

function mouseClicked() {

  drawRandom();

}

​