replacing a loop with recursion

[linucksrox]

I'm trying to replace my a loop in a exponent function but I'm not sure how to go about doing it... thanks for any help

double power(double a, double b)
{
    double pow = 1;
    int i = 1;
    char flag = OFF;            /* the reason for using (char) is that it only takes up 1 byte */

    if (b == 0)
      return a;

    if (b < 0)
      flag = ON;

    if (i <= b)                      /* this loop is what's messed up... */
      pow *= power(a, i + 1);

    if (flag == ON)
      pow = 1 / power(a, -b);

    return pow;
}

that loop would normally be

for (i = 1; i <= b; i++)
  pow *= a;

but that's my poor attempt at recursion...

[ggs]

try power(a, b-1);

i dun think you need i anymore

[linucksrox]

thanks, I finally got it. I still don't quite understand it, but it works fine.

double power(double a, double b)
{
    double pow = a;
    char flag = OFF;            /* the reason for using (char) is that it only takes up 1 byte */

    if (b < 0)
      flag = ON;

    if (b > 0)
      pow *= power(a, b - 1);

    if (flag == ON)
      pow = 1 / power(a, -b);

    if (b == 0)
      pow = 1;

    return pow;
}