Shorten my code, i want to compare my work to yours.

[jesi]

any idea on how to shorten this code?

#include <iostream>
using namespace std;

int main()
{

    int num1, num2, num3;

    cout << "Enter three numbers: \n ";
    cin >> num1;
    cin >> num2;
    cin >> num3;

    cout << num1 << "\n";
    cout << num2 << "\n";
    cout << num3 << "\n";
  
    return 0;

    }

[fiji885]

You can use a for loop and arrays.

#include <iostream>

int main() {
  const size_t foo = 3;
  int bar[foo];
  std::cout << "Enter " << foo << " numbers: ";
  for(size_t i = 0; i < foo; i++)
    std::cin >> bar[i];
  for(auto i : bar)
    std::cout << i << std::endl;
  return 0;
}

$ g++ main.cpp 
$ ./a.out 
Enter 3 numbers: 30 60 90
30
60
90
$ 

[Cheddar99]

This would be shorter, but I tend to think the best code, in any project, is the most readable and the most maintainable; that is, I prefer clarity over brevity if there's a choice.

Still, being as you asked:

#include <iostream>

int main(){
    int n[3];
    std::cout << "Enter three numbers:\n";
    std::cin >> n[0] >> n[1] >> n[2];
    std::cout << "\n" << n[0] << "\n" << n[1] << "\n" << n[2] << "\n";
return 0;
}

Enter three numbers:
10
4
56

10
4
56

or maybe ...

#include <iostream>

int main(){
    int n[3];
    std::cout << "Enter three numbers:\n";
    std::cin >> n[0] >> n[1] >> n[2];
    for(auto i:n) std::cout <<n[i] << "\n";
return 0;
}

[dhayden]

It's usually helpful to look carefully at the problem and solve exactly what's for and no more. So while my solution is pedantic, I hope it illustrates the idea.

- Since you don't do anything with the numbers, there's no need for an array.
- Unless you really need the output to go the screen then there's no need to delay printing it:

#include <iostream>

int main(){
    int n;
    std::cout << "Enter three numbers:\n";
    for (int i=0; i<3; ++i) {
        std::cin >> n;
        std::cout << n << '\n';
   }
}

To go even further, you could just print "Enter three numbers:\n" and then copy cin to cout.

[Duthomhas]

@jesi
So far, yours is the cleanest code here that doesn’t change program behavior.

Focus on writing clean, easy-to-read code over being tricky. The only variation I might consider is chaining the operators:

#include <iostream>
using namespace std;

int main()
{

    int num1, num2, num3;

    cout << "Enter three numbers: \n ";
    cin >> num1
        >> num2
        >> num3;

    cout << num1 << "\n"
         << num2 << "\n"
         << num3 << "\n";

}

If you are inclined to scrunch stuff on one line then you could do that too... but scrunching makes things less readable, IMHO.

Hope this helps.