How to pass an input from c++ function to the main function - c++

Question

i want to take an input from c++ function and return it to the main function
, i've already tried to do it but the function returns zero , any idea ?
#include<iostream>
using namespace std;
int input( int x);
int main()
{
int number;
input(number);
cout<<number;
}
int input (int x)
{
cin>>x;
return x;
}

Answer 1

you need to pass by reference
void input (int & x)
{
cin>>x;
}
or use the return value
int main()
{
int number;
number = input();
cout<<number;
}
int input ()
{
cin>>x;
return x;
}

Answer 2

You can change your function to make it take x by reference:
void input (int& x)
{
cin>>x;
}
This way, you don't even need to return x, because your function will update its value as it is passed by reference.

Answer 3

So, let's get it from the begining :
It any function, all its variables are temporary and only accessible in this function's scope unless you use a pointer or a reference(c++ only)
So what happen when you call your function is that a copy of number's is created into x
Also, the return statement of a function is used to... return values! Yeah, weird uh?
So actually you don't even need to send any parameter to your function and just take its result :
#include<iostream>
using namespace std;
int input();
int main()
{
int number = input(); // Takes what the return statement gives
cout<<number;
}
int input ()
{
int x;
cin>>x;
return x;
}
Here's another way by using c++'s references :
#include<iostream>
using namespace std;
void input( int& x);
int main()
{
int number;
input(number);
cout<<number;
}
int input (int& x)//Takes number's address
{
cin>>x;
}