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islessequal() Function with Example in C++

C++ islessequal() function: Here, we are going to learn about the islessequal() function with example of cmath header in C++ programming language?
Submitted by IncludeHelp, on May 17, 2020

C++ islessequal() function

islessequal() function is a library function of cmath header, it is used to check whether the given first value is less than or equal to the second value. It accepts two values (float, double or long double) and returns 1 if the first value is less than or equal to the second value; 0, otherwise.

Syntax of islessequal() function:

In C99, it has been implemented as a macro,

    macro islessequal(x, y)

In C++11, it has been implemented as a function,

    bool islessequal (float x      , float y);
    bool islessequal (double x     , double y);
    bool islessequal (long double x, long double y);

Parameter(s):

x, y – represent the two values to be checked whether x is less than or equal to the y.

Return value:

The returns type of this function is bool, it returns 1 if x is less than or equal to y; 0, otherwise.

Example:

    Input:
    float x = 10.0f;
    float y = 15.0f;
    
    Function call:
    islessequal(x, y);
    
    Output:
    1

C++ code to demonstrate the example of islessequal() function

// C++ code to demonstrate the example of
// islessequal() function

#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    cout << "islessequal(-5.0f, -2.0f)  : " << islessequal(-5.0f, -2.0f) << endl;
    cout << "islessequal(10.0f, 20.0f)  : " << islessequal(10.0f, 20.0f) << endl;
    cout << "islessequal(10.0f, 10.0f)  : " << islessequal(10.0f, 10.0f) << endl;
    cout << "islessequal(-10.0f, -20.0f): " << islessequal(-10.0f, -20.0f) << endl;

    float x = 10.0f;
    float y = 5.0f;

    // checking using the condition
    if (islessequal(x, y)) {
        cout << x << " is less than or equal to " << y << endl;
    }
    else {
        cout << x << " is not less than or equal to " << y << endl;
    }

    x = 10.0f;
    y = 10.0f;

    if (islessequal(x, y)) {
        cout << x << " is less than or equal to " << y << endl;
    }
    else {
        cout << x << " is not less than or equal to " << y << endl;
    }

    return 0;
}

Output

islessequal(-5.0f, -2.0f)  : 1
islessequal(10.0f, 20.0f)  : 1
islessequal(10.0f, 10.0f)  : 1
islessequal(-10.0f, -20.0f): 0
10 is not less than or equal to 5
10 is less than or equal to 10