c++, pass by ref

gistfile1.cpp

// pass by ref example

#include <iostream>
using namespace std;

/*
	store memory address using pointer type variable.
	int* x : x is a variable to store memory address
	of another variable.
	*x : use this syntax to access value from memory address.

	int* a and *a are two completly different things.
*/
void swap(int* a, int* b)
{
	int p = *a;
	*a = *b;
	*b = p;
}
int main(){
	int a = 10;
	int b = 20;
	cout<<a<<" "<<b<<endl;
	/*
		pass memory address using &
		&x = memory address of variable x
	*/
	swap(&a,&b); 
	cout<<a<<" "<<b<<endl;
}