To make sure that you *always* return a negative number in JavaScript, you can do *either* of the following:

## Using Unary Negation Operator

You can convert the number to its absolute form, and then negate it using the unary negation operator (`-`

):

-Math.abs(n)

This would convert a positive number to negative and ensure that an already negative number remains unchanged. For example, you can use this in the following way:

// ES6+ const neg = (num) => -Math.abs(num); console.log(neg(1234)); // -1234 console.log(neg(-1234)); // -1234

You can rewrite the "`neg`

" function as a function declaration/statement (instead of using arrow function), to support versions of ES prior to version 6.

## Using Arithmetic Operators

You can convert the number to its absolute form, and then negate it either by:

- Multiplying or dividing the number by
`-1`

, or; - Subtracting the number from
`0`

.

Math.abs(n) * -1

Math.abs(n) / -1

0 - Math.abs(n)

This would convert a positive number to negative and ensure that an already negative number remains unchanged. For example, you can use these in the following way:

// ES6+ const neg = (num) => Math.abs(num) * -1; console.log(neg(1234)); // -1234 console.log(neg(-1234)); // -1234

// ES6+ const neg = (num) => Math.abs(num) / -1; console.log(neg(1234)); // -1234 console.log(neg(-1234)); // -1234

// ES6+ const neg = (num) => 0 - Math.abs(num); console.log(neg(1234)); // -1234 console.log(neg(-1234)); // -1234

You can rewrite the "`neg`

" function as a function declaration/statement (instead of using arrow function), to support versions of ES prior to version 6.

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