function setup() {

  createCanvas(400, 400);

}

​

function draw() {

  background(220);

  text(test, 10, 10);

}

​

let count = 0;

function mousePressed() {

  console.log(test.length);

  test[test.length] = [];

  test[test.length-1].push(parseInt(random(10)));

​

}

​