So currently I have an Array here, and I want to make some modification of the last item and push it back it. Here I have this code: (example is simplified)

```
var array = [
                 [ [0,1,2], [3,4,5] ]
            ];

//other stuff...

var add = array[0].slice(); //to clone the array (but not working as expected)
add[0][0] = 10;
array.push(add);

console.log(array);

```

And here's the result

　　　　　　　![enter image description here](https://i.stack.imgur.com/5bCcb.png)

As you can see, both the 1st and 2nd item have its first item changed to `10`. How can I solve this problem? I have already cloned the array.