Unlock the Power of Ceiling Values in C++

Understanding the ceil() Function

The ceil() function is a powerful tool in C++ that helps you compute the smallest possible integer value that’s greater than or equal to a given argument. Defined in the <cmath> header file, this function takes a single parameter: a floating-point number whose ceiling value needs to be computed.

Syntax and Parameters

The syntax of the ceil() function is straightforward:

double ceil(double num)

Where num is the floating-point number whose ceiling value is to be computed.

Return Value

The ceil() function returns a single value: the smallest possible integer value that’s greater than or equal to num.

Prototypes and Header Files

The prototypes for ceil() are defined in the <cmath> header file, making it easy to integrate into your C++ projects.

Practical Examples

Let’s take a look at some examples to see the ceil() function in action:

Example 1: Floating-Point Numbers

When working with floating-point numbers, the ceil() function returns the smallest possible integer value that’s greater than or equal to the input number.

double num = 3.7;
double ceiling = ceil(num);
std::cout << "Ceiling of " << num << " is " << ceiling << std::endl;

Output:

Ceiling of 3.7 is 4

Example 2: Integral Types

While the ceil() function can be used with integral types, it’s not typically done in practice since the result will always be the same as the input value.

int num = 5;
double ceiling = ceil(num);
std::cout << "Ceiling of " << num << " is " << ceiling << std::endl;

Output:

Ceiling of 5 is 5

Related Functions

If you’re working with floor values, be sure to check out the floor() function in C++, which returns the largest possible integer value that’s less than or equal to a given argument.

double num = 3.7;
double floorValue = floor(num);
std::cout << "Floor of " << num << " is " << floorValue << std::endl;

Output:

Floor of 3.7 is 3