How to write C++ code for rounding up a number?

In C++, you can achieve rounding up using the following code:

#include <iostream>
#include <cmath>

int main() {
    double num = 3.14;
    int roundedNum = ceil(num);

    std::cout << "原始数值: " << num << std::endl;
    std::cout << "向上取整后的数值: " << roundedNum << std::endl;

    return 0;
}

The ceil() function from the header file is used here to perform the rounding up operation.