# fabs() in C++

• Difficulty Level : Expert
• Last Updated : 09 Apr, 2018

The fabs() function returns the absolute value of the argument.
Mathematically |a|. If a is value given in the argument.

Syntax:

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```double fabs(double a);
float fabs(float a);
int fabs(int a);
```

Parameter:

• The fabs() function takes a single argument, a whose absolute value has to be returned.

Return:

• The fabs() function returns the absolute value of the argument.

Error:

• It is mandatory to give both the arguments otherwise it will give error
no matching function for call to ‘fabs()’ like this.
• # CODE 1

 `// CPP code to illustrate``// fabs() function``#include ``#include `` ` `using` `namespace` `std;`` ` `int` `main()``{``    ``int` `a = -10, answer;`` ` `    ``answer = ``fabs``(a);``    ``cout << ``"fabs of "` `<< a ``         ``<< ``" is "` `<< answer << endl;`` ` `    ``return` `0;``}`

OUTPUT :

```fabs of -10 is 10
```

# CODE 2

 `// CPP code to illustrate``// fabs() function``#include ``#include `` ` `using` `namespace` `std;`` ` `int` `main()``{``    ``long` `int` `a = -35;``    ``double` `answer;`` ` `    ``answer = ``fabs``(a);``    ``cout << ``"fabs of "` `<< a << ``" is "` `         ``<< answer << endl;`` ` `    ``return` `0;``}`

OUTPUT :

```fabs of -35 is 35
```

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