The round() function returns the integer that is closest to the argument, with halfway cases rounded away from the ending zero.


  • The num parameter must be a double,float, or long double.
  • The return value will be an integer.
  • If the decimal in num is 0.5 or higher, the closest integer greater than num is returned.


The following example showcases the round() function being applied to two double values, one of which is a halfway case:

#include <iostream>
#include <cmath>
int main()
double num1 = 9.23;
double result1;
result1 = std::round(num1);
std::cout << "The result of round(9.23) is " << result1 << "\n";
double num2 = 4.5;
double result2;
result2 = std::round(num2);
std::cout << "The result of round(4.5) is " << result2 << "\n";

This produces the following output:

The result of round(9.23) is 9
The result of round(4.5) is 5

Codebyte Example

The following example is runnable and rounds the halfway case away from zero:



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