#include <stdio.h>
#include <math.h>
 
void print(char *name, double x)
{
    unsigned long long h = *(unsigned long long *)&x;
 
    printf("%s = %03llX|%013llX (%.16f)\n", name, h >> 52, h << 12 >> 12, x);
}
 
int main(void)
{
    double q[] = {2, 3, 3.9999999999999996};
    double p, x, y, z;
 
    for (int i = 0; i < sizeof(q) / sizeof(q[0]); i++) {
        for (int j = 0; j < 2; j++) {
            if (j == 0) {
                p = q[i];
                x = sqrt(p);
                printf("[p = %.17g]\n\n", p);
                printf("x = sqrt(p)\n");
            } else {
                x = z;
                printf("x = z\n");
            }
 
            y = p / x;
            z = (x + y) / 2;
            print("x", x);
            print("y", y);
            print("z", z);
            printf("x %s z\n\n", x == z ? "==" : "!=");
        }
    }
    return 0;
}

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