Any better way of implementing this recusively?

[AmericanD]

I have a function that does intermediate calculations to a greatest common divisor deal. and here is how its implemented iteratively (see exteuc() function) .

i tried to implement it recursively too, (see exteuc2() function) . feel free to look at it and give me suggestions if i can improve my recursive implementation in any way. even though it works out. i ask because i'm doing c++ programming after a long long time now.

the function takes 2 numbers and 3 arrays of int size 3 each. copyarr just shifts the contents of arrays left by 1. its needed because the array is of size 3 and as i only need 3 values at one time to do calculations on.

int exteuc2(int num1, int num2, int* x, int* y, int* r)
{
  int q, tmp;
  r[1] = (num1 * x[1]) + (num2 * y[1]);
  tmp = r[1];
  if (tmp > 0)
  {
	q = r[0] / r[1];
	x[2] = x[0] - (q * x[1]);
	y[2] = y[0] - (q * y[1]);
	copyarr(x);
	copyarr(y);
	copyarr(r);


	exteuc2(num1, num2, x, y, r);
  }
  return q;
}
int exteuc(int num1, int num2, int* x, int* y, int* r)
{
  int q;
  while (( r[1] = (num1 * x[1]) + (num2 * y[1])) != 0)
  {
	q = r[0] / r[1];
	x[2] = x[0] - (q * x[1]);
	y[2] = y[0] - (q * y[1]);
	copyarr(x);
	copyarr(y);
	copyarr(r);
	}
  return q;
}

edit : i thought i'ld add copyarr function.

here
void copyarr(int* p)
{
p[0] = p[1];
p[1] = p[2];
}