Method push

stacks/triple-stack.js:24–28

(stack, value)

  }

  push(stack, value) {
    let idx = this._getLength(stack) * 3 + stack - 1;
    this._array[idx] = value;
    ++this._lengths[stack - 1];
  }

  pop(stack) {
    let length = this._getLength(stack),