I have given instructions to write some code and i have to follow the comments giving and i get stuck and some point so can anyone tell me what i did wrong

/*

* Returns the percent change from the original to the desired servings.

* The percent is expressed as a decimal. i.e.:

* 1 = 100%

* 0.5 = 50%

* 1.5 = 150%

* If either of the serving values is 0, a value of 1 serving is assumed.

*

* To calculate the number of servings, the following formula is used:

*

* Desired Servings =

* | Desired Servings / Original Servings | - 0.1 *

* (1 - | Original Servings / Desired Servings | ))

*

* where | x | is the absolute value of x

*

* original - number of servings the recipe was designed for

* desired - the number of servings wanted

*

* returns the % change that should apply to all of the ingredients.

*/

double changeServings(int original, int desired)

{

//stops any division by 0

if (original == 0)

{

original = 1;

}

if (desired == 0)

{

desired = 1;

}

//end check

// get absolute value for | Original Serving / Desired Servings |

double rate = original / (double)desired;

if (rate < 0)

rate = -rate;

//modify -1 below to be your new calculated value.

return (rate - 0.1 * (1 - rate));

}