how to change the demial place of a double in c++ code example

Example 1: how to specify how many decimal to print out with std::cout

#include <iostream>
#include <iomanip>

int main()
{
    double d = 122.345;
    std::cout << std::fixed << std::setprecision(2) << d;
}

//result that get print out: 122.34

Example 2: how to print 5 precision float in c++

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

int main() 
{
    // This code helps you to print a number with desired decimal
    double Number=10.3454;
    printf("%.3lf",Number);

    return 0;
}