p;lease need to know how the output is 5 i have an exam and i am lost

1. #include <iostream>
using namespace std;
int change(int x);
int main()
{
int y=3,z;
cout<<change(y)<<endl;
z=change(5);
cout<<'t'<<z<<endl;
return 0;
}
int change(int x)
{
cout<<x+2<<endl;
x++;
return x;