Question: ```
// program to count down numbers to 1
function countDown(number) {

  // display the number
  console.log(number);

  // decrease the number value
  const newNumber = number - 1;

  // base case
  if (newNumber > 0) {
    countDown(newNumber);
  }
  console.log(newNumber);
}

countDown(4); 

// output => 4 3 2 1 0 1 2 3

```

I can't visualize what happens after the if condition. I mean I understand that there is "loop" with countDown(newNumber). But I don't understand why there is the output 0 1 2 3. I know I can put an else keyword, but I'd like to understand why JS engine after finishing the recursion it prints four times console.log(newNumber).

Answer: 
You can simplify your function.

```js
function countDown(number) {

  if (number > 0) {
    console.log(number);
    countDown(--number);
  }

}

countDown(4);
```
this way ?

```js
countDown( 4 )

// program to count down numbers to 1
function countDown(num)
  {
  if (num<1) return
  console.log(num)
  countDown(--num)
  }
```