void main()
{
GetSincos(30.0,dSin,dCos);
cout<<"The value of dSin is"<<dSin<<endl;
cout<<"The value of dcos is"<<dCos;
}

What is meant by accessing it directly? The value or the reference. If it should be reference I could use some further explanation… The way I understood the sentence is, that once the value is copied, it can be accessed easily.”

You might translate this as “… is slower than directly accessing the value that the pointer/reference refers to”.

So:

int i;
int n=10;
int directVals[n] = 0;
int pVals = &directVals;

for (i=0; i<n; i++) {
  directVals[i] = 1 // A - direct access is faster
  *pVals[i] =1       // B - accessing through de-referenced pointer is a little slower than A
}
 

But, this speed to access data must be balanced against the time that it takes to copy data into a "direct" variable, as in pass-by-value. For large n, the suggestion is that the copy time will outweight the speed-of-access time. What's the break-even threshold? Good question!

—> It tells the coder whether he needs to worry about the function changing the value of the argument

What is meant by accessing it directly? The value or the reference. If it should be reference I could use some further explanation… The way I understood the sentence is, that once the value is copied, it can be accessed easily.

Btw I should mention that I like this site very much. Especially the quizzes, though there could be more of them ;-)