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Computes the absolute value of a number.


x: the number


x: if x is greater than or equal to 0.

-x: if x is less than 0.


Because of the way the abs() function is implemented, avoid using other functions inside the brackets, it may lead to incorrect results.

abs(a++);   // avoid this - yields incorrect results

a++;          // use this instead -
abs(a);       // keep other math outside the function

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