freebsd-nq/contrib/libf2c/libF77/pow_qq.c
2003-07-11 03:42:19 +00:00

32 lines
416 B
C

#include "f2c.h"
longint
pow_qq (longint * ap, longint * bp)
{
longint pow, x, n;
unsigned long long u; /* system-dependent */
x = *ap;
n = *bp;
if (n <= 0)
{
if (n == 0 || x == 1)
return 1;
if (x != -1)
return x == 0 ? 1 / x : 0;
n = -n;
}
u = n;
for (pow = 1;;)
{
if (u & 01)
pow *= x;
if (u >>= 1)
x *= x;
else
break;
}
return (pow);
}