call by reference in C++ functions code example

Example 1: calling by reference c++

void fun(int *a)
{
   *a = 10;
}

Example 2: calling by reference c++

void fun2(int& a) 
{
    a = 5;
}

int main()
{
    int b = 10;
    fun2(b); 

    // now b = 5;
    return 0;
}