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#define FREESTEAM_BUILDING_LIB
#include "common.h"
/* ipow: public domain by Mark Stephen with suggestions by Keiichi Nakasato */
double ipow(double x, int n){
double t = 1.0;
if(!n)return 1.0; /* At the top. x^0 = 1 */
if (n < 0){
n = -n;
x = 1.0/x; /* error if x == 0. Good */
} /* ZTC/SC returns inf, which is even better */
if (x == 0.0)return 0.0;
do{
if(n & 1)t *= x;
n /= 2; /* KN prefers if (n/=2) x*=x; This avoids an */
x *= x; /* unnecessary but benign multiplication on */
}while(n); /* the last pass, but the comparison is always
true _except_ on the last pass. */
return t;
}
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