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# Bouncing Balls

## [Bouncing Balls](https://www.codewars.com/kata/5544c7a5cb454edb3c000047)

A child is playing with a ball on the nth floor of a tall building. The height of this floor, *h*, is known.

He drops the ball out of the window. The ball bounces (for example), to two-thirds of its height (a bounce of 0.66).

His mother looks out of a window 1.5 meters from the ground.

How many times will the mother see the ball pass in front of her window (including when it's falling *and* bouncing?

## Three conditions must be met for a valid experiment:

* Float parameter "h" in meters must be greater than 0
* Float parameter "bounce" must be greater than 0 and less than 1
* Float parameter "window" must be less than h.

**If all three conditions above are fulfilled, return a positive integer, otherwise return -1.**

### Note:

The ball can only be seen if the height of the rebounding ball is strictly greater than the window parameter.

### Example:

```
- h = 3, bounce = 0.66, window = 1.5, result is 3

- h = 3, bounce = 1, window = 1.5, result is -1 

(Condition 2) not fulfilled).
```

## Solutions

#### 👴 C

```c
int bouncingBall(double h, double bounce, double window)
{
    if(!(h > 0 && bounce > 0 && bounce < 1 && window < h))
      return -1;

    char counter = 1;
    double bounce_h = h;

    while(1)
    {
      bounce_h = bounce_h*bounce;
      if(bounce_h >= window)
        counter+=2;
      else
        break;
    }

    return counter;
}
```