How to display numbers of the same length in C++?

Question

C++ / C#

cout << std::hex << " " << num;
It is necessary that 8 digits be output.
That is, the number f23a87 was displayed as 00f23a87

Answer 1

#include <iostream>
#include <iomanip>

using namespace std;

int main()
{
    int num = 0xf23a87;
    cout << hex << setfill('0') << setw(8) << num;

    return 0;
}

Answer 2

en.cppreference.com/w/cpp/io/manip/setfill