#include <iostream>using namespace std;int main(){ int n; cin >> n; if(n % 2 == 0) cout << n << endl; else cout << n * 2 << endl; return 0;}

This is a simple C++ program that reads an integer from the user, checks if it's even or odd, and then prints the number itself if it's even, or twice the number if it's odd.

Here's a step-by-step explanation:

1. #include <iostream>: This line includes the iostream library,