Add number of hours to 24 hour clock

This function adds a number of hours to a 24 hour clock:

/**
 * @param {Integer} now The current hours
 * @param {Integer} add The number of hours to add
 */
function addHours(now, add){
    var h = (now + add) % 24;

    return h < 0 ? 24 + h : h;
};

• addHours(2, 5) //7

• addHours(23, 5) //4

• addHours(23, -5) //18

• addHours(72, 3) //3

• addHours(0, 0) //0

The output should always be an integer in the range of 0 - 23.

I can't see any problem with it, but maybe you can. Please let me know if it can be improved or if there are any bugs.

Tiny question ;)

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As @Rotora mentioned, now is not a fantastic parameter name, it conveys that I need to only pass who late it is 'now', add is a verb, also not brilliant as parameter naming goes

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addHours( -500 , -100 ) returns -0, is that what you want ?

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You have 4 lines of comment, 3 lines of code, 1 blank line, perhaps you have to much comment ? Try to not need comments by working harder on parameter names.

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Since adding is commutative ( order does not matter ), I would consider naming the function sumHours and name the parameters hours1 and hours2

function sumHours(hours1, hours2){
    var sum = (hours1 + hours2) % 24;
    return sum < 0 ? 24 + sum : +sum;
};

StackExchange Code Review Q#55989, answer score: 5