Pass by reference vs value examples

gistfile1.txt

void addTwo (int a){
  a = a+2;
}

void duplicate (int a, int& b, int& c){
	addTwo(a);
	c = b;
	cout << a;

}

int x = 5;
int y = 6;
int z = 7;

duplicate(x,y,z);

cout << x…y…z

int a = 2;
int b = 3;
int answer;
void passByReference(int a, int b, int& answer1){
	answer = a+b;

}
passByReference(a,b,answer);
cout << answer;