What is nanl() in C/C++?

The nanl function removes the NaN(not-a-number) value from the input string. It returns the NaN value of type long double.

Library for C++

#include<cmath>

Library for C

#include<math.h>

Syntax

 long double nanl (const char* str);

Parameters

str - a string value

Return Value

It returns a NaN value which is in long double.

Code

#include <iostream>
#include <cmath>
#include <cstring>
using namespace std;
int main()
{
    float nanValue;
    //generating generic NaN value by passing an empty string
    nanValue = nanl("");
    cout << "nanValue: " << nanValue << endl;
    float nanValue1;
    nanValue1 = nanl("12343");
    cout << "nanValue: " << nanValue1 << endl;
    float nanValue2;
    nanValue2 = nanl("abc");
    cout << "nanValue: " << nanValue2 << endl;
  
    return 0;
}

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