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#include <math.h>
#include <inttypes.h>
double frexp(double x, int *e)
{
union { double d; uint64_t i; } y = { x };
int ee = y.i>>52 & 0x7ff;
if (!ee) {
if (x) {
x = frexp(x*0x1p64, e);
*e -= 64;
} else *e = 0;
return x;
} else if (ee == 0x7ff) {
return x;
}
*e = ee - 0x3fe;
y.i &= 0x800fffffffffffffull;
y.i |= 0x3fe0000000000000ull;
return y.d;
}
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