Greedy Algorithm Change Making

[Spreegem]

So I have to make a greedy algorithm to find the fewest number of coins needed to make change for any n cents. I have an infinite number of quarters(25 cents), dimes (10 cents), nickles (5 cents), and pennies (1 cent). This is the algorithm I came up with, it works fine but I was wondering whether this is the best solution?

make_change(int change)
{
	while(change > 25)
	{
		change = change - 25;
		quarters++;
	}

	while(change > 10)
	{
		change = change - 10;
		dimes++;
	}

	while(change > 5)
	{
		change = change - 5;
		nickles++;
	}

	while(change >= 1)
	{
		change = change - 1;
		pennies++;
	}

	return 1;
}

I am having some trouble with coming up with a function to find the number of operations performed to make change for any n>0 cents. I know that for each coin there is a check to see if we should make change in that denomination, and if so there is a subtraction and an addition. But I don't know how to turn that into some sort of function to calculate the number of operations performed. Any hints? Thanks a bunch for any help.